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F150 rev limiter

dirttracker18

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So i have mainly been a GM guy but that is for another post. Due to a good deal I recently purchased a 2004 F150. I have to admit I think it tows way better than my 2002 silverado did. Not for power but jsut the way the trailer feels behind the truck.

So I came up to an intersection that I know the second lane ends at. I really wanted to get by the vehicle beside me as they tend to drive way under the speed limit. The light turns green and he sets off at a strong pace. I guess we were thinking the same thing.

So I small the shifter into 1 (automatic) to hold for a few more RPM. This usually gives me a little advantage as most vehicles shift a little early for a safety margin. However I am horrified to find out that this truck has a rev limiter set at 5000 rpm. Serioulsy, 5000 rpm?? It was still pulling hard when it bounced and I almost hit the dash. A quick shift kept me in front of the other guy but that is not the point. Now I like the idea of a rev limiter to keep you out of trouble but 5000 seems very low to me especially when the turck had power yet.

I also know I can get a tunner and up the limiter but why would they put it so low. My GMs would rev well into the 6 k range before limiting out. Where are the Dodges at? Why 5k for the Ford? Are they that weak?
 
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JunkBonds

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How about driving sanely and not street racing?

I see drivers everyday doing this thinking they are more important and rushing to get to the head of the line while those who are courteous are pushed back by the right lane bandits.

Then you won't hit the rev limit.
 

G_P

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5k pretty high. what did you do floor it when the light went green and try to drag race?

I dont ever think I have even revved my jeep that high and have no problem passing.
 

Squankum

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Doesn't it depend on whether it's worth revving that high? I don't suspect a truck has a cam oriented towards that rpm range. I suspect it's the cam profile they're thinking of, not the valve springs, that they're worried about. As in, "there's no ****** point going beyond this rpm range, use the next gear."

I'm assuming this is a modern OHC modular Ford V-8, I don't keep up. RPM wouldn't worry me at all with the modern stuff.
 

fatkidracer

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GM LS truck motors rev to around 5,800 stock. the limiter in the Ford 3v truck motor is 5,100 if my memory serves me right. there not that far apart. and yes it is still making power at that rpm but it signs off right around 5,500 rpm.

if you wanna race people from light to light towing a trailer buy a diesel, i always win those races. ( I do not condone street racing for all the safety Sam’s on here)
 

Falcon67

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Sounds about the right RPM to me. I'm sure you can re-program that as long as you don't mind buying a motor if you-know-what goes on. The computer will (should) also shut off at somewhere between 110 and 120 MPH, IIRC. I don't recall what RPM my 2004 5.4 shifts at on the drag strip. I think it's right under 5K. All I know is that it's a ***** to cut a light with.
 
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dirttracker18

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How about driving sanely and not street racing?

I see drivers everyday doing this thinking they are more important and rushing to get to the head of the line while those who are courteous are pushed back by the right lane bandits.

Then you won't hit the rev limit.

Anyway . . .

No one had to be pushed back anywhere as I was well clear of the vehicle in the other lane when I changed lanes. As far as street racing, I did not even have to exceed the speed limit to get in front of the other vehicle. If he had pushed hard for the spot I would have gladly given it to him. he did not but was harder off the line than I would have expected. The lane ends so i either hit it and get in front or slow down and join the back of the pack.

Let me guess, you are one of those guys that would have done what you could to make sure I did not get that lane? I do keep my racing on the track and am an in favor of such activities being there. I do not care to follow the pack at 10 to 20 km/h under the speed limit if I do not have too. I live out that highway and get stuck behind some lally gagger rubber necker too many days to count.

I have owned the truck for 2 months now and this was the first time I pushed it that hard so you can keep your uninformed comments to yourself, get out of the left lane and let the faster traffic by you :thumbup:
 
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dirttracker18

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Sounds about the right RPM to me. I'm sure you can re-program that as long as you don't mind buying a motor if you-know-what goes on. The computer will (should) also shut off at somewhere between 110 and 120 MPH, IIRC. I don't recall what RPM my 2004 5.4 shifts at on the drag strip. I think it's right under 5K. All I know is that it's a ***** to cut a light with.

I don't see me going that fast in my truck :lol_hitti

I may, however buzz the upper limit of RPM in first from time if needed. I was just totally caught off guard as it dropped off just as I was about to shift at what I thought was a reasonable rpm :dunno:

Well now I know.
 
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dirttracker18

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5k pretty high. what did you do floor it when the light went green and try to drag race?

I dont ever think I have even revved my jeep that high and have no problem passing.

I wouldn't have too if that 5.4l had some more torque at a lower rpm but it seems too many of these V8s today are all HP and limited TQ. I always hated that about my 5.3l GM, torque was too high to be useful. The F150 is a little lower on the curve but not a lot :)
 

jeffk14

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dirttracker; my 2006 with 373 gears and the 5.4 does fine just starting off in drive. There have been a few times when I felt like I had to "get on it" from a stop and It did just fine. Those engineers are purty smart folks. I'll bet that if you had tried that same maneuver in drive, you'd have been just fine.

IMHO, 5K RPM is plenty for a stock V8 in a truck. Especially with all that whirlygigvariableoverheadcamtimingshit that the newer Fords have goin' on.
 
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Falcon67

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I wouldn't have too if that 5.4l had some more torque at a lower rpm but it seems too many of these V8s today are all HP and limited TQ. I always hated that about my 5.3l GM, torque was too high to be useful. The F150 is a little lower on the curve but not a lot :)

I don't know about that - my Super Crew pulls the race car and trailer @ 5500lbs up to highway speed pretty quick. To Dallas and back I average 11 MPG loaded.

Not that "fast" - truck averages 10.70 at about 70+ in the 1/8 mile. You have to "squeeze" it off the line to keep from blowing the tires off.
 

mhm993

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You need the 4.10 rear on an f150 to really launch it. Just don't look at the gas gauge.
 

BigAl62

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Yes you can get a programmer and reset the rev limiter, but as stated by fatkidracer there isn't much to be gained by going much higher (the camming on a truck engine is for torque low in the rpm range) and you may do more harm than good. And the speed limiter is set for 108mph (or approx. 175km/h) and it will set a code in the computer if you go that fast (I don't remember if it is a clearable code, it's not on some vehicles!) and you can reset that with a programmer also. As for racing, I'll leave that up to you and your driving style. Just some food for thought.

EDIT: If you do reset your speed limiter don't forget that the tires on your vehicle may not be rated for the increased speed!
 
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NUTTSGT

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I've never come close to hitting the rev limiter on my truck. I left it in Drive the one time that I did take it to the track. The truck shifted on it's own fine.


BTW, don't bother buying a K&N air filter for it. It'll kill the gas mileage by 1.5-2 mpg. Stick in for towing but for everyday driving just use a regular filter.
 

Sterff

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Get a programmer and change it. I have mine set at 4050 (diesel though).
 

jhelrey

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Here is a hint from a Ford owner... Hit the tow/haul *** button.
 

andrew_94

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How about driving sanely and not street racing?

I see drivers everyday doing this thinking they are more important and rushing to get to the head of the line while those who are courteous are pushed back by the right lane bandits.

Then you won't hit the rev limit.


:lol_hitti

Theres a line between racing and doing what you need to do. I'm still on my learners permit and I've figured this out. OP is absolutely sane in what he did.

It's called discretion. Use the gas pedal to get yourself out of a bad situation.
 

JunkBonds

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The light turns green and he sets off at a strong pace. I guess we were thinking the same thing.

So I small the shifter into 1 (automatic) to hold for a few more RPM. This usually gives me a little advantage as most vehicles shift a little early for a safety margin. However I am horrified to find out that this truck has a rev limiter set at 5000 rpm. Serioulsy, 5000 rpm?? It was still pulling hard when it bounced and I almost hit the dash. A quick shift kept me in front of the other guy

ONTARIO REGULATION 455/07

RACES, CONTESTS AND STUNTS

Consolidation Period: From July 26, 2011 to the e-Laws currency date.

Last amendment: O. Reg. 360/11.

Definition, “race” and “contest”
2. (1) For the purposes of section 172 of the Act, “race” and “contest” include any activity where one or more persons engage in any of the following driving behaviours:
1. Driving two or more motor vehicles at a rate of speed that is a marked departure from the lawful rate of speed and in a manner that indicates the drivers of the motor vehicles are engaged in a competition.


Too bad a cop didn't see you then you could have explained to him you weren't really racing.

I love it how some people justify their acts.
 

jeffk14

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ONTARIO REGULATION 455/07

RACES, CONTESTS AND STUNTS

Consolidation Period: From July 26, 2011 to the e-Laws currency date.

Last amendment: O. Reg. 360/11.

Definition, “race” and “contest”
2. (1) For the purposes of section 172 of the Act, “race” and “contest” include any activity where one or more persons engage in any of the following driving behaviours:
1. Driving two or more motor vehicles at a rate of speed that is a marked departure from the lawful rate of speed and in a manner that indicates the drivers of the motor vehicles are engaged in a competition.


Too bad a cop didn't see you then you could have explained to him you weren't really racing.

I love it how some people justify their acts.

Good grief! The man started a thread to ask a question about what he perceived to be a performance issue with his truck. You were not there to SEE what went on when he accelerated to gain a position in traffic. Give it a rest.

I love how when some people start to "preach", they don't know when to stop.
 

JunkBonds

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ok...I am wrong.

I apologize.

You are obviously entitled to drag race on the street.

Just tell the cop the guys at GJ say its ok.

NOT

Many people of have been killed by people racing on the street. It is not ok and there is no way to justify it.
 
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suprvee

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ok...I am wrong.

I apologize.

You are obviously entitled to drag race on the street.

Just tell the cop the guys at GJ say its ok.

NOT

Many people of have been killed by people racing on the street. It is not ok and there is no way to justify it.

Do you make love with your pants on? :evil:
 
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dirttracker18

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ok...I am wrong.

I apologize.

You are obviously entitled to drag race on the street.

Just tell the cop the guys at GJ say its ok.

NOT

Many people of have been killed by people racing on the street. It is not ok and there is no way to justify it.

Boy you are some piece of work aren't you.

OK you want to play that way I'll play. Thanks for the clarification with the regs. However as per your quote ( yours not mine ) since I did not exceed the speed limit I was not stunt driving. No one said anything about drag racing but you. I said I took the opportunity to get by another vehicle and did so under the posted speed limit.

Now you can go back to ******* off all the other drivers around you by keeping everyone in the left lane just under the speed limit by boxing them in with the car in the right lane.

Do you have anything to contribute to the rev limited conversation? No? Great, then off you go to whatever it is that you do :)
 
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So i have mainly been a GM guy but that is for another post. Due to a good deal I recently purchased a 2004 F150. I have to admit I think it tows way better than my 2002 silverado did. Not for power but jsut the way the trailer feels behind the truck.

So I came up to an intersection that I know the second lane ends at. I really wanted to get by the vehicle beside me as they tend to drive way under the speed limit. The light turns green and he sets off at a strong pace. I guess we were thinking the same thing.

So I small the shifter into 1 (automatic) to hold for a few more RPM. This usually gives me a little advantage as most vehicles shift a little early for a safety margin. However I am horrified to find out that this truck has a rev limiter set at 5000 rpm. Serioulsy, 5000 rpm?? It was still pulling hard when it bounced and I almost hit the dash. A quick shift kept me in front of the other guy but that is not the point. Now I like the idea of a rev limiter to keep you out of trouble but 5000 seems very low to me especially when the turck had power yet.

I also know I can get a tunner and up the limiter but why would they put it so low. My GMs would rev well into the 6 k range before limiting out. Where are the Dodges at? Why 5k for the Ford? Are they that weak?
boy , does the mod motor like to eat itself alive
 

ishiboo

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Dumbest. Thread. Ever.

Anyway . . .

No one had to be pushed back anywhere as I was well clear of the vehicle in the other lane when I changed lanes. As far as street racing, I did not even have to exceed the speed limit to get in front of the other vehicle. If he had pushed hard for the spot I would have gladly given it to him. he did not but was harder off the line than I would have expected. The lane ends so i either hit it and get in front or slow down and join the back of the pack.

Let me guess, you are one of those guys that would have done what you could to make sure I did not get that lane? I do keep my racing on the track and am an in favor of such activities being there. I do not care to follow the pack at 10 to 20 km/h under the speed limit if I do not have too. I live out that highway and get stuck behind some lally gagger rubber necker too many days to count.

I have owned the truck for 2 months now and this was the first time I pushed it that hard so you can keep your uninformed comments to yourself, get out of the left lane and let the faster traffic by you :thumbup:

It's simple. If you want to speed up a bit to get in front of someone that's fine. If it is to the point where you are attempting to manually shift an automatic transmission (stupid) and you need to modify your 5,000 RPM rev limiter for normal driving, something is wrong with your driving habits. You do not need to increase the rev limit in a truck for normal driving conditions, period.

From what I can tell, you've watched one too many Trailer Park Boys up there in the far north.

:lol_hitti

Theres a line between racing and doing what you need to do. I'm still on my learners permit and I've figured this out. OP is absolutely sane in what he did.

It's called discretion. Use the gas pedal to get yourself out of a bad situation.

Doing what you need to do? Why would he NEED to have a higher rev limiter? Who needs to use 5,000 RPM in normal driving and manually shifting an automatic transmission!? How was it a "bad situation"? He wanted to be in front, period.

I hope your parents read this and put a long delay on your actual license :p

Honestly, this thread is insane.
 

garfunkle24

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Doing what you need to do? Why would he NEED to have a higher rev limiter? Who needs to use 5,000 RPM in normal driving and manually shifting an automatic transmission!? How was it a "bad situation"? He wanted to be in front, period.

I hope your parents read this and put a long delay on your actual license :p

Honestly, this thread is insane.

WTF does "need" have to do with anything, anyway? He drove legally and as far as I can gather without further info, with due care and attention. What do you care if wants to do clutch dumps at 10k RPM?
 
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dirttracker18

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Dumbest. Thread. Ever.



It's simple. If you want to speed up a bit to get in front of someone that's fine. If it is to the point where you are attempting to manually shift an automatic transmission (stupid) and you need to modify your 5,000 RPM rev limiter for normal driving, something is wrong with your driving habits. You do not need to increase the rev limit in a truck for normal driving conditions, period.

From what I can tell, you've watched one too many Trailer Park Boys up there in the far north.



Doing what you need to do? Why would he NEED to have a higher rev limiter? Who needs to use 5,000 RPM in normal driving and manually shifting an automatic transmission!? How was it a "bad situation"? He wanted to be in front, period.

I hope your parents read this and put a long delay on your actual license :p

Honestly, this thread is insane.

^^^^^^^^ Then why are you here?????

I love these guys that have nothing constructive to add to a conversation (and misread I might add but I will get to that) but insist on saying something anyway.

I never said I wanted to increase the rev limiter. I simply asked about it being at such a low point (in comparison to other vehicles of the same caliber and engin size).

Why is it stupid to shift an automatic? If it was soooo stupid you would not have the option. But you do, sooo . . .

I shift it because I can.

Why would you use 5k in normal dirinv conditions, I guess you would not. However I was passing another vehicle (once again under the speed limit) and had to either finish the pass or move to the back of a long line as the lane was ending up the road.

I don't watch trailer park boys and resent what you are trying to say. I don't go around making personal attacks on you and have been engaged in conversation with you before so I am not sure why the attack?

If you really don't like the conversation, go to another thread.

Perhaps we can make nice somewhere else. :dunno:
 

Dragster Racer

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:lol_hitti

Theres a line between racing and doing what you need to do. I'm still on my learners permit and I've figured this out. OP is absolutely sane in what he did.

It's called discretion. Use the gas pedal to get yourself out of a bad situation.

Pedal may have gotten him into that situation. LOL.
Anyhow. Like was said before, the LS motors like to rev. Even my 6L likes to buzz to make power. Just the way they are. Fords not as bad. Even so, my Chevy delays the shift a little longer than I would like in tow haul. I'm not afraid of the revs hurting anything....but late shifts hurt mileage and slow acceleration. Let the computer shift it, IMO. I let the air shifter shift the dragster, and it crosses the line at 8,100.
 

ishiboo

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^^^^^^^^ Then why are you here?????

I love these guys that have nothing constructive to add to a conversation (and misread I might add but I will get to that) but insist on saying something anyway.

I never said I wanted to increase the rev limiter. I simply asked about it being at such a low point (in comparison to other vehicles of the same caliber and engin size).

Why is it stupid to shift an automatic? If it was soooo stupid you would not have the option. But you do, sooo . . .

I shift it because I can.

Why would you use 5k in normal dirinv conditions, I guess you would not. However I was passing another vehicle (once again under the speed limit) and had to either finish the pass or move to the back of a long line as the lane was ending up the road.

I don't watch trailer park boys and resent what you are trying to say. I don't go around making personal attacks on you and have been engaged in conversation with you before so I am not sure why the attack?

If you really don't like the conversation, go to another thread.

Perhaps we can make nice somewhere else. :dunno:

Kind of the nature of Internet forums; you have to have a thick skin. I don't think you're dumb, don't take it personally, I just question this particular action. I'm sure you can find LOTS of actions I do as moronic :) Don't take anything I say personally, it's just my opinion of your action, not what I think of you. The big narrative was irrelevant to the question, which I guess you expected ONLY to hear why it's so "low", so it kind of invited commentary just by its presence.

Automatics are set up to be manually shifted for driving conditions like towing, slippery conditions, etc... and so people can feel that the vehicle is more "sporty", not so you can eek some extra RPMs out beyond redline. Interestingly, many of the automatics with a "sport" manual mode where you can "paddle shift" are actually slower when used that way then letting the car shift, as it protects itself from your actions.

To answer ONLY your question then, 5,000 RPM is not that low of a rev limiter IMHO for a stock domestic truck V8. It could also be limited differently based on what gear your in, the fact that you're shifting manually, etc. It's set "so low" because the higher the RPMs, the greater the chance of valve train failure and the lower the service life of the engine... Ford's covering its ***.
 
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dirttracker18

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I didn't like the tow/haul in my Silverado much. As you said, shift was pretty late even under light load. But I still used it.

Someone else mentioned the tow/haul in the Ford. I have the tow package and no tow/haul?
 
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dirttracker18

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Ishiboo

Appreciate the reply. Respect back to you.

I am pretty certain 5k isnot the redline in this truck but where they choose to put in a "safe" shift point. The truck was still pulling hard and I was very surprised as my Chevrolet higher.
 

andrew_94

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Dumbest. Thread. Ever.



It's simple. If you want to speed up a bit to get in front of someone that's fine. If it is to the point where you are attempting to manually shift an automatic transmission (stupid) and you need to modify your 5,000 RPM rev limiter for normal driving, something is wrong with your driving habits. You do not need to increase the rev limit in a truck for normal driving conditions, period.

From what I can tell, you've watched one too many Trailer Park Boys up there in the far north.



Doing what you need to do? Why would he NEED to have a higher rev limiter? Who needs to use 5,000 RPM in normal driving and manually shifting an automatic transmission!? How was it a "bad situation"? He wanted to be in front, period.

I hope your parents read this and put a long delay on your actual license :p

Honestly, this thread is insane.

Why does he need to have a higher rev limiter? Why does my car redline at 6,500 rpm?

When i put my foot down, I'm telling the car that I need all the power it has to offer. Thats what its there for.

In regard to the license comment, I drive with my mother on my learners permit. Anything I've learned I've learned from her. Both of us have flawless driving records.
 

ishiboo

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Why does he need to have a higher rev limiter? Why does my car redline at 6,500 rpm?

Because of the design of your engine including the rotating mass, strength of parts, compression, fuel type, intake design, etc., it varies. Some manufacturers are less and more agressive.

When i put my foot down, I'm telling the car that I need all the power it has to offer. Thats what its there for.

All vehicles have limits, geared toward longevity and fuel economy.

In regard to the license comment, I drive with my mother on my learners permit. Anything I've learned I've learned from her. Both of us have flawless driving records.

Once you get old enough you'll realize that having a flawless driving record does not equate to being a good driver, like many things in life.
 

jeffk14

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I didn't like the tow/haul in my Silverado much. As you said, shift was pretty late even under light load. But I still used it.

Someone else mentioned the tow/haul in the Ford. I have the tow package and no tow/haul?

On the Ford, I consider the "OD Off" button as their answer to tow/haul mode. If someone else knows the difference, I'm all ears.
 

ishiboo

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I didn't like the tow/haul in my Silverado much. As you said, shift was pretty late even under light load. But I still used it.

Someone else mentioned the tow/haul in the Ford. I have the tow package and no tow/haul?

Tow/haul is optimized for towing, not for you to like it. It firms up the shifts by increasing the line pressure, as well as delaying shifts a bit for higher RPMs.

But it can actually make it less fun to drive for you... the benefit is, less heat is generated in the clutch packs means the transmission lasts longer, a bit better economy, etc.
 

ishiboo

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On the Ford, I consider the "OD Off" button as their answer to tow/haul mode. If someone else knows the difference, I'm all ears.

OD Off disables overdrive, necessary on some loads on some vehicles at higher speeds. It takes strain off the transmission by running at a higher engine speed, at the cost of fuel economy.

Tow/Haul varies by vehicle, on the Allison 1000 installed in the Duramax trucks, it increases line pressure, applies the torque converter clutch far sooner, increases the number of allowable gears to downshift to when decelerating, and changes the shifting points for higher revs. It also downshifts more aggressively, using the engine to brake/slow the vehicle instead of the brakes to help slow the load without brake fade.
 

jeffk14

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OD Off disables overdrive, necessary on some loads on some vehicles at higher speeds. It takes strain off the transmission by running at a higher engine speed, at the cost of fuel economy.

Tow/Haul varies by vehicle, on the Allison 1000 installed in the Duramax trucks, it increases line pressure, applies the torque converter clutch far sooner, increases the number of allowable gears to downshift to when decelerating, and changes the shifting points for higher revs. It also downshifts more aggressively, using the engine to brake/slow the vehicle instead of the brakes to help slow the load without brake fade.
Thanks. Seems I had an oversimplified view of GM's tow/haul mode.
 

Falcon67

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Merkel, TX
On the Ford, I consider the "OD Off" button as their answer to tow/haul mode. If someone else knows the difference, I'm all ears.

I tow with OD on. The truck came with the tow package, the ****** seems fine with it. I have a little over 80K on it now and it went on it's first 500+ mile round trip at 11,500 GCVW with 12 miles on the odometer. Except for this year, it has pulled that load nearly every other weekend since 2004. With the exception of the window regulators, it's been a great truck. Would buy another tomorrow.
 

wintermute

Well-known member
Joined
Sep 4, 2011
Messages
450
Location
Mount Vernon, WA
Interesting, I wouldn't expect a 5100 RPM limiter either. Maybe because you put it in 1 instead of leaving it in drive? Who know how many parameters the PCM alters based on the gear selection?
 

jeffk14

Well-known member
Joined
Aug 17, 2010
Messages
1,631
Location
GA
I tow with OD on. The truck came with the tow package, the ****** seems fine with it. I have a little over 80K on it now and it went on it's first 500+ mile round trip at 11,500 GCVW with 12 miles on the odometer. Except for this year, it has pulled that load nearly every other weekend since 2004. With the exception of the window regulators, it's been a great truck. Would buy another tomorrow.

I tow a travel trailer that's about 6500 lbs when fully loaded. I've always towed with OD off. I've been afraid that doing otherwise would be too hard on the transmission. Maybe I've just been wasting gas.
 
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