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2-post lifts for crewcab longbed diesel pick-ups

sierradmax

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Sep 5, 2005
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461
Location
Rhode Island
I know this thread has been discussed in length from previous topics but I thought I would raise up the argument, yet again.

I have a crewcab longbed duramax SRW. 172" wheelbase. I was on route 95 the other day and thought I would bring it to a scale.

Steer axle 4380#
Drive axle 2970#

Granted the truck has HD steel bumpers, 35" tires, full tank of fuel, and about 400# in the bed, those numbers equate to about 7400# truck weight and a 60/40 C.O.G.

With the wheelbase and 60/40 C.O.G., this puts the C.O.G. at 70" rear of the steer axle and 102" front of the drive axle, which was about 1" from my original assumption for my 2 post lift placement.



Speaking with lift manufacturers, a 9,000# 2-post would be enough but I opted for a 10,000#, which would safely balance a rated 2,500# on each arm. Currently, with the truck's weight centered in line with the 2-post lift, the front arms, in theory, support about 2,200# each. Maybe a bit more on the drivers side but you get the idea....

Following a post from someone who commented on the above picture, the rear lift arms SHOULD support the front leaf perch to the drive axle, per ALI LP Guide.

http://thsauto.weebly.com/uploads/4/3/6/1/43610783/lifting_points_guide.pdf

Although my front lift arms are 3 stage Symmetrical arms, the rear's are two stage and cannot reach the perch unless the lift is moved towards the rear of the truck a minimum of 10". The trucks frame "turns-up" just past the cab to support the bed. The picture above shows the location of the rear arm pad placement just prior to the frame rail "turning-up".

For the sake of argument (and I won't get into the math), shifting the 2-post lift 10" would, by my math, be right at 2,500# for the front arms and exceed the rated capacity. Not to mention, It would have 5,000# hanging in the front, 2,400# hanging in the back yielding, unbalanced, lateral forces against the lift columns.

Perhaps I'm thinking about this too much but should these trucks stay away from 2 post lifts, should they only be lifted on 12,000# rated lifts and higher, or are there lift manufacturers who make 10,000# and higher lifts with 3 stage, longer rear lift arms?
 
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Sycan

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Aug 5, 2015
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414
My Challlenger has 2 stage arms but will reach farther back than that. That actually looks kind of iffy having the lifting points so close.
 

thecj3man

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Sep 21, 2009
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East TN
I have a long bed Dodge crew cab and it is amazing how similar in weight it is to yours. My truck has 4520# on the front and 2980# on the back for an even 7500# total. This is a bone stock 2006 Dodge 2500 with a full tank of fuel and no extra stuff except a gooseneck hitch in the back. I pick mine up with my 10K Challenger lift and haven't had any issues reaching the pickup points. My lift does have the 3 stage rear arms though. I have had a harder time picking up smaller cars with short wheelbases.
 
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sierradmax

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Messages
461
Location
Rhode Island
My Challlenger has 2 stage arms but will reach farther back than that. That actually looks kind of iffy having the lifting points so close.

I agree but in the photo above, the truck lifts perfectly level. And, from manufacturers websites, videos, etc., I see them lifting long wheelbase pick-ups using the same lift points as I have. Not to say they're doing it right or wrong but I'm sure they're experiencing similar situations.

http://www.challengerlifts.com/CL12_photo.shtml#!prettyPhoto/3/

 

zkdiesel

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Oct 6, 2013
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8,319
Location
chicagoland cornfields
Rotary 10k and 12k spo lifts with three stage arm option(standard on12).
They will lift ford, Chevy or dodge at the desired pickup locations and give you still quite a few inches either way unlike other manufacturers. Routinely lift crew cab dump trucks up to f550 on my spo12's
 

Backyard Imports

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Oct 21, 2015
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Location
western WA
I worked at Chevy for some time and nobody in the shop picked up the trucks by the spring perches. All trucks were lifted up by the frames. Due to the way some of the frames curved upwards around the rear of the cab, the lift arms often looked just like this picture. In the many years that I was there it was never a problem.

A little off topic but why is that lift positioned so that the nose of the truck is against the wall? I would think that it would make more sense to set it back towards the door so that you could work under the hood while on the lift. Even if the rear bumper was just clearing the roll up door, you could at least open the door to get more space.
 

WhiffySpark

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6,252
You're fine. 12k works better. You could love it forward more until the door opens just in front of the column but you can with how you have it set up
 
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sierradmax

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Sep 5, 2005
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461
Location
Rhode Island
I worked at Chevy for some time and nobody in the shop picked up the trucks by the spring perches. All trucks were lifted up by the frames. Due to the way some of the frames curved upwards around the rear of the cab, the lift arms often looked just like this picture. In the many years that I was there it was never a problem.

A little off topic but why is that lift positioned so that the nose of the truck is against the wall? I would think that it would make more sense to set it back towards the door so that you could work under the hood while on the lift. Even if the rear bumper was just clearing the roll up door, you could at least open the door to get more space.

The ladder rack just clears the overhead door opener. I should have went with a jackscrew opener. There's enough room for me to squeeze between the truck & wall.
 

lakeroadster

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Jan 19, 2015
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Location
Central Colorado
I know this thread has been discussed in length from previous topics but I thought I would raise up the argument, yet again.

Link to previous thread: Center of Gravity Chevy R-30 truck (lift placement)

Perhaps I'm thinking about this too much but should these trucks stay away from 2 post lifts, should they only be lifted on 12,000# rated lifts and higher, or are there lift manufacturers who make 10,000# and higher lifts with 3 stage, longer rear lift arms?

Does the manufacturer of your lift have optional 3 stage arms?

I worked at Chevy for some time and nobody in the shop picked up the trucks by the spring perches. All trucks were lifted up by the frames.

Perhaps Chevrolet has a bulletin that shows acceptable lift points, and that varies in comparison to ALI spec's?
 
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walrus

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Maine
I lift my 2013 2500hd, extended cab, 8ft bed, aluminum Reading tool body with Rotary spo10. Front lift pads on frame, rear on front of springs. 3 stage arms its over 9ft from front lift point to rear lift point. Still not sure its right but its what it says in book. Lifts it no problem but makes me nervous under it
 
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Ign

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Jul 7, 2006
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Butte Peak ND
Yes, you're overthinking it.

Yes, my BP XPR-10XC has 3 stage rear arms, but I don't know if that's a function of the Xtra drive thru clearance.

Even so, I can rarely get the front rear spring hanger on most trucks.

On my old '97 PSD crew I actually custom bent some pieces of square tube and welded them to the frame where it curves up to effectively level the frame and provide a place for lift pads.

Oh and I've learned to totally ignore the ALI book that came with my lift - half the time the **** it calls out simply isn't possible.
 

jsaw

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Oct 11, 2008
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Location
Geneva, N.Y.
I worked at Chevy for some time and nobody in the shop picked up the trucks by the spring perches. All trucks were lifted up by the frames. Due to the way some of the frames curved upwards around the rear of the cab, the lift arms often looked just like this picture. In the many years that I was there it was never a problem

I worked at a Chevy dealer also. I saw a guy had both lift arms on the flat part of the frame of a regular cab long box truck.
He was rotating the tires, he took one front wheel off and stood there holding the tire as the back bumper headed towards the floor.

After seeing that happen I always try to lift the truck under the front perch of the rear spring
 

lakeroadster

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Central Colorado
Yes, you're overthinking it.... I've learned to totally ignore the ALI book that came with my lift ....

I worked at a Chevy dealer also. I saw a guy had both lift arms on the flat part of the frame of a regular cab long box truck.
He was rotating the tires, he took one front wheel off and stood there holding the tire as the back bumper headed towards the floor.

After seeing that happen I always try to lift the truck under the front perch of the rear spring

Just looking at the photo above, the rear lift arms are so far forward that the scenario Jsaw is describing is not only possible, but probable. Being a crew cab 2wd would further exacerbate the problem. 4x4's would be less likely, due to the transferr case and front axle weights.

sierradmax I am betting you could grab the rear bumper, with the truck as shown on the lift in the photo, front wheels removed, and by pulling down, get it to teeter on the rear lift arms.

 
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dave89iroc

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Mar 25, 2015
Messages
706
Location
outside Detroit, Michigan USA
large trucks I always pull them forward far enough that the drivers door will open, then can safely grab far enough to the rear and far enough forward

generally the center of gravity on any truck other than a standard cab is right around the b pillar or slightly rearward, in your picture the CG is probably only 12-18 inches forward of the rear lift point, not safe for any major work



in fact, those safety stands at the front? you would be better off with them at the rear
 

WhiffySpark

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Oct 22, 2009
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This is a 4wd duramax diesel. But same principle. This is a 12k rotary makes it easier
 

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mikes02ls1

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Sep 26, 2015
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427
Location
Casa Grande, AZ
I know this thread has been discussed in length from previous topics but I thought I would raise up the argument, yet again.



I have a crewcab longbed duramax SRW. 172" wheelbase. I was on route 95 the other day and thought I would bring it to a scale.



Steer axle 4380#

Drive axle 2970#



Granted the truck has HD steel bumpers, 35" tires, full tank of fuel, and about 400# in the bed, those numbers equate to about 7400# truck weight and a 60/40 C.O.G.



With the wheelbase and 60/40 C.O.G., this puts the C.O.G. at 70" rear of the steer axle and 102" front of the drive axle, which was about 1" from my original assumption for my 2 post lift placement.







Speaking with lift manufacturers, a 9,000# 2-post would be enough but I opted for a 10,000#, which would safely balance a rated 2,500# on each arm. Currently, with the truck's weight centered in line with the 2-post lift, the front arms, in theory, support about 2,200# each. Maybe a bit more on the drivers side but you get the idea....



Following a post from someone who commented on the above picture, the rear lift arms SHOULD support the front leaf perch to the drive axle, per ALI LP Guide.



http://thsauto.weebly.com/uploads/4/3/6/1/43610783/lifting_points_guide.pdf



Although my front lift arms are 3 stage Symmetrical arms, the rear's are two stage and cannot reach the perch unless the lift is moved towards the rear of the truck a minimum of 10". The trucks frame "turns-up" just past the cab to support the bed. The picture above shows the location of the rear arm pad placement just prior to the frame rail "turning-up".



For the sake of argument (and I won't get into the math), shifting the 2-post lift 10" would, by my math, be right at 2,500# for the front arms and exceed the rated capacity. Not to mention, It would have 5,000# hanging in the front, 2,400# hanging in the back yielding, unbalanced, lateral forces against the lift columns.



Perhaps I'm thinking about this too much but should these trucks stay away from 2 post lifts, should they only be lifted on 12,000# rated lifts and higher, or are there lift manufacturers who make 10,000# and higher lifts with 3 stage, longer rear lift arms?



How high are your ceilings?


Sent from my iPhone using Tapatalk
 

foibgshop

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Joined
Jun 18, 2024
Messages
1
I know this thread has been discussed in length from previous topics but I thought I would raise up the argument, yet again.

I have a crewcab longbed duramax SRW. 172" wheelbase. I was on route 95 the other day and thought I would bring it to a scale.

Steer axle 4380#
Drive axle 2970#

Granted the truck has HD steel bumpers, 35" tires, full tank of fuel, and about 400# in the bed, those numbers equate to about 7400# truck weight and a 60/40 C.O.G.

With the wheelbase and 60/40 C.O.G., this puts the C.O.G. at 70" rear of the steer axle and 102" front of the drive axle, which was about 1" from my original assumption for my 2 post lift placement.



Speaking with lift manufacturers, a 9,000# 2-post would be enough but I opted for a 10,000#, which would safely balance a rated 2,500# on each arm. Currently, with the truck's weight centered in line with the 2-post lift, the front arms, in theory, support about 2,200# each. Maybe a bit more on the drivers side but you get the idea....

Following a post from someone who commented on the above picture, the rear lift arms SHOULD support the front leaf perch to the drive axle, per ALI LP Guide.

http://thsauto.weebly.com/uploads/4/3/6/1/43610783/lifting_points_guide.pdf

Although my front lift arms are 3 stage Symmetrical arms, the rear's are two stage and cannot reach the perch unless the lift is moved towards the rear of the truck a minimum of 10". The trucks frame "turns-up" just past the cab to support the bed. The picture above shows the location of the rear arm pad placement just prior to the frame rail "turning-up".

For the sake of argument (and I won't get into the math), shifting the 2-post lift 10" would, by my math, be right at 2,500# for the front arms and exceed the rated capacity. Not to mention, It would have 5,000# hanging in the front, 2,400# hanging in the back yielding, unbalanced, lateral forces against the lift columns.

Perhaps I'm thinking about this too much but should these trucks stay away from 2 post lifts, should they only be lifted on 12,000# rated lifts and higher, or are there lift manufacturers who make 10,000# and higher lifts with 3 stage, longer rear lift arms?
Where is the pic? I have the same issue with my truck.
 

firebirdparts

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Joined
Jun 8, 2016
Messages
10,607
Location
Kingsport, TN
Savage thread bump. Welcome to the forum!

If you can't, you can't. Disregarding the truck's center of gravity is obviously okay, and that'll help some, but you still may not be able to reach to the rear springs. The super duties have a big frame kickup and really just gives you no good place for the rear lift arm. So for most of us, I guess we just lift on the flat part of the frame and then you can go back to thinking about where the center of gravity is.

In the thread you quoted, it sure seemed like turning the truck around would have solved it.
 
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