2 post vs 4 post lifts

[chaingang]

This may have been covered here in the past but I would like opinions on 2 posts vs 4 posts lifts. I will be building soon and need to consider footings for where my lift will be and I have not decided on a style yet. I am concerned that a two post lift will be a problem when pulling an engine and trans out. As in will I have to reset the vehicle with the weight difference? Do they have a tendency for the car or truck to be unstable while doing heavy wrenching. Can one lift be used for a smaller car as well as a fullsize PU. I know, not at the same time. Also ground clearance will be an issue cause if it ain't low it ain't sitting right. What about working around the columns, ramps etc of both lifts? Would parking a second vehicle be a problem under a two post? This will often be the case. Is a six inch floor thick enough without extra footings for anchoring either lift? What about brands? This is not a commercial shop just the backyard shop I have always wanted for my, and it seems, my two sons projects. It does keep them out of trouble. Any other incite would be greatly appreciated.

 

[Aahz]

oh boy....Lots of questions in this post......!!! Let's start with some basics...twin post lifts are the most popular types of lifts on the market for mechanical work. Of all the surface mount lifts, they are the most versatile for mechanical work. Whenever you use this type of lift, it is IMPERATIVE that you balance the vehicle correctly and never overload the arms. (A 10,000 lbs two post lift has a rated capacity of 2500 lbs. per arm) If you buy a Certified Lift ( www.autolift.org ), it should come with a book that shows you where the proper pickup points are for different bodystyles and frames. Some of these lifts also have a "wheel spotting dish" that can be bolted on the floor to help you set different wheelbase vehicles in the recommended position. Everything else being equal, (ie. vehicle is loaded properly) then pulling an engine or ****** is not an issue. (The vehicle will not slide or flip when the weight is removed.)

Small vs. large vehicles on a two post....depends on a few factors...1.) By small, do you mean low profile? Most 2 post lifts have an pad height of between 4" and 5". Some (like the Rotary SPOA10-RA) go as low as 3-5/8". If you need to go lower than that, you need a floor jack to raise the car high enough to set the arms. 2.)Large vehicles (up to 1 tons or so) typically have running boards that will interfere with putting the lifting pads in the proper positions. To deal with these issues, you need a height extension adapter. Almost all lift manufacturers offer these as an option. 3.) Large vehicles (ie. custom top vans, etc.) offer the challenge of being too tall for the typical lift to raise all the way up. Some manufacturers offer "Extended Height" lifts...these are extensions on the top of the lift that raise the overhead limit switch up so that you can raise a high topped vehicle to full rise. They are usually 1' or 2' taller than the standard configuration. (A standard lift is usually about 12' tall...so a 1' extension would make it 13', 2' extension 14', etc.)

Parking a vehicle under a 2 post lift can be done, but remember you are picking up by the frame for the top vehicle. This means the suspension is going to hang...If the lift has a 78" rise (for example) the bottom of the tires may be sitting around 60". (The bottom car would have to be less than 60" to fit under it.) Additionally....MAKE SURE THE TOP VEHICLE IS SET ON THE SAFETIES. Nothing worse than losing a hydraulic line in the middle of the nite and finding out you have two wrecked cars instead of just one....

 

[bmwpower]

I have my F250 on my Rotary SP010 right now with no engine installed and an old 302 in the bed... no problems. It helps to have a symmetrical lift when doing this as the center of gravity is closer to the middle of the 2 posts.

 

[chaingang]

by small I mean compact vs full size pick up. We have an eclectic group of cars at my place. One son has an 83 ranger and a 64 Fairlane. The other has an 84 Mustang GT and a 67 F100 shortbed while I have an 82 Capri Drag car, 85 Turbo coupe TBird daily driver, Pro Street long bed 67 F100 and a 40 Ford Deluxe Coupe that I am Street rodding, along with an Explorer for the wife. With this info will one particular 2 post pick up these cars, unibody and full frame alike. What about the 40 that probably is not in any manual for lift points.

 

[bmwpower]

Ask a Rotary dealer. If the dealer isn't able to answer, they usually contact Rotary.

I had my dealer check for me since some stuff is not published in their guidelines.

As for the "all purpose" lift... I would go symmetrical as these seem to fit more vehicles out of the box as opposed to assymetrical units (which sometimes require special length arms for certain vehicles).

 

[mikeyr]

gee based on the responses so far, I guess this board much prefers the 2-post lifts.

Me? I like living so give me 4 nice solid legs on the ground and no worries about tiping a car over. 4 wheels on a car, 4 posts on any lift I am going to get under.

Ask around about like you are doing, you will find 2 vs. 4 is a religious experience with very little tolerance for the other type. As to the argument that its easier to do suspension work on a 2-post, yes its true and I will admit that but unless you are a professional shop which you already said you are not then its not a big deal to do suspension work and again if it not a professional shop then do like me, do the suspension work right the first time and you wont have to do it very often.

No clearance issues on a 4-post, you can move a 4-post around in the shop which I think is important because a shop is a living breathing space and what works for you today might not next year, its nice to just "move the lift", no weight distribution issues either. I also move my motorcycle onto one of the ramps and lift the bike to make it easy to work on, try that on 2-post.

If I sound like a 4-post fanatic, I am not, they both have their features and both serve their purpose, I just want to point out that there are other points of view.

 

[C_F]

I think I'd like to have one of each to use for a couple years...then I can give my honest opinion on this matter.

 

[David Hawkins]

A 4 post also doesn't require reinforced concrete as the load is more distributed and not cantilevered.

You can't beat a 2 post for brake and suspension work, but I'll be buying a 4 post for the convenience of not having the lift tied to one spot in the shop.

 

[carguy123]

The biggest complaints I hear about the 4 post is the double jacking.

You have to jack the whole car up then you have to jack up the front or rear to get to the wheels &/or suspension. Anyone found a quick, easy and inexpensive way to do the second jacking?

I have my slab poured and am looking for a lift right now. Worth has a "special" on a 2 post they are running now that looks good. I had thought to go a 2 post because I have Zero need for storage but do have a need for ******/engine swaps.

This is the first thread I've ever seen where a symmetrical was given a thumbs up. What about the prob of opening the doors when the car is on the lift with symmetrical?

 

[wilbilt]

You can't beat a 2 post for brake and suspension work

Personally, I prefer a single post inground for that, but that's probably not an option for most people (myself included).

I spent a lot of time working under 4-post lifts (alignments, mostly) and they can't be beat for safety and stability. They are a pain, because the runways and posts are always in the way. To be of much use they need to have rolling jacks or jack trays at least, which adds to the expense.

That being said, I chose a 4-post for my home shop. It is out back in pieces awaiting a place to set it up. It is an older Bend-Pak with the overhead ram, chains instead of cables, and multiple safety locks in each column.

I have never felt comfortable working around 2-post abovegrounds, especially the asymmetric ones. The weight and balance factors depend a lot on the concrete and the anchor bolts, and I don't take anything for granted when a multi-ton load is over my head.

 

[TNToy]

They both have their place. We've got everything covered in this discussion at work. I use an a-symmetical 9K rotary 2-post for 90% of what I do at work... Which is pretty much any repair on our dealerships late-model unibody sedans.

I've had a powerstroke excursion on my rack, you just load it more like a symmetrical lift, with the vehicle as far forward as the front legs allow. That said, I wouldn't want to do much more that brake/suspension/oil changes with that setup, as the vehicle rocked a bit if you hung on the front bumper and pushed. On a symmetrical lift big vehicles are much more stable. If you plan to work on a lot of fullsize trucks, get a symmetrical.

We use the drive-on racks (an in-ground and a 4-post) for alignments and for something else you can't do on a 2-post lift: Finding suspension noises. I drove a customers car the other day that had a freaky rattle over large bumps from the R/F tire. I couldn't disagnose on my 2-post - checked all suspension parts, etc and EVERYTHING was tight.

So I put it on the 4-post and you could recrate the sound by smacking the sidewall with a dead-blow mallet. I stood on the brakes with the car 4 feet in the air while another guy did the swinging. The noise went away when you applied the brakes. Came back when you released them. Turned out whatever shop had just done a brake job on it hadn't properly installed the inboard brake pad into the caliper, and it rattled over bumps...

Try diagnosing that without being able to peek under the car with the vehicles weight on the suspension.

With all that said, I use each type of lift regularly, and I plan on installing a lift at home eventually. And it'll be a symmetrical 2-post, since I do a lot of work on fullsize trucks. If I didn't, it'd be an a-symmetrical.

With a lightweight vehicle like the Ranger and the Mustang you mentioned, which weigh around a third of the typical 9K capacity, I'll spot it more like an a-symmetrical - shift the car back enough to easily open & close the doors. You'll still be way below the weight limit on each arm of the lift. The only issue you run into is wether or not the arms will collapse/extend enough to reach the pickup points.

BTW, on a unibody vehicle like the mustang, if I'm just doing brake work, I'll set the feet under the pinch-weld as close to the front & rear tires as possible. Makes for a quick lift, and works very well. If you're going to be hanging from the vehicle or pullling trannies, rack it further in on both sides. That way, even if disaster strikes and the vehicle shifts over 6 inches, the foot slides off the sub-frame and might crush the floorboard or something, but it can't fall off the rack to the ground.

With regards to the '40... I installed a new brake switch my brothers restored 49 Chevy this weekend. Fullsize trucks and old cars with big ladder frames are the easiest to rack. You set the feet so they catch the frame as far forward & back as you can get. That's about it. Very stable.

Since you mentioned fullsize trucks, I'd be looking at a 2-post symmetrical if I were in your place. You might have to **** in your gut since the door will only open 16" or so on an F-250 parked waaaay forward for porper balance, but the rest of the time, it's a non-issue, and I wouldn't want to do much work on a F250 balanced on an a-symmetrical.

 

[TNToy]

Forgot to mention:

Get one with feet that flip-up if possible. On some low cars or trucks with step-bars, the arm of the lift will contact the rocker panel before the foot is up against your lift point.

You can slap a piece of 2x4 in there to do the same thing, but you don't have to worry about a flip-up foot squirting out like you would with a block of wood sitting in between two smooth metal surfaces.

 

[Notch1988]

I went with the asymmetrical 2 post in my garage. I worked at a dealership as well many years ago and we had a single four post and all the others were symmetrical 2 posters. I hated getting in and out of cars with the symmetrical, and I just plain hated working on cars with the 4 post. I feel almost claustrophobic under a 4 post, plus all the ducking and the width of the ramps are always a pain to work around. I would only buy a four post if all I needed was storage, otherwise a 2 post all the way.

 

[TNToy]

I went with the asymmetrical 2 post in my garage. I worked at a dealership as well many years ago and we had a single four post and all the others were symmetrical 2 posters. I hated getting in and out of cars with the symmetrical...

Good point. It all depends on the lift. The only one we've got has enough travel in it's arms I can load a sedan like an asymmetrical if it's positioned right.

I think it really comes down to one thing once you get the PITA 4-posters out of your head: If you primarily work on 1-ton light trucks, get a symetrical, if it's usually cars and the occasional 1/2-ton truck... a 9K rated asymmetrical will leave you much happier.

There's a reason most Toyota/Honda/Volvo/BMW/etc shops use a-symmetrical 2-post lifts. They work the best on cars.

 

[Aahz]

Lots of good points here in this board....(Anyone want to be a lift salesman for me??) I want to add a bit, although it's been stated pretty loud and clear so far...

Four post lifts are great for limited projects and some are great for parking. There are different kinds of four posts, just like there are different types of two posts.
A.) Parking Lift four post ---ideal for LIGHT duty mechanical work and parking. These lifts are not typically built for doing mechanical work...can be purchased from as low as $1600 to as much as $3700.00. Very few are ALI/ ETL Certified....limited options available on most models. Most versions require removal of the drive-up ramps to get clearance for parking underneath.

B.) Commercial Grade 4 Post---Ideal for heavy mechanical work, brakes, wheels and oil changes. Limited room between the runways (usually about 40-48") to do undervehicle work. Not recommended for engine replacements because the runways and crossbeams get in the way of on engine hoist. When the ramps are on the ground, vehicle will sit 6-12" higher than it would be on a flat stall. Expect to bang your head a few times doing oil changes prior to remembering the cross-beam connecting the two ramps in front. (Stitches are a distinct possibility). There are options for "open front" 4 post to prevent this from happening, but added cost. If youy purchase a 4 post with an overhead cylinder, (Bend Pak, Worth, etc. make these types) save some money for door dings and or crushed doors when vehicle is raised with the door open. Always recommended to purchase a 4 post with the hydraulic cylinder under the runway. Make sure the unit you look for has the proper wheelbase for the vehicles you might want to pick up. Typically range from the 150" range to 200" range. With a dragster...you also need to check the width of the vehicle vs. the width of the ramps. Drive-up ramps will need to be modified to allow underhoist parking. If you have low-profile vehicles, ask for an option that allows extended drive-up ramps...otherwise you may bottom out the vehicle as you drive up the ramps.

C.) Last but not least are alignment style 4 posts....basically the same as a commercial grade, but also includes the slip plates and radius gauges.

I don't want anyone to think I'm opposed to 4 posts...but they are a different animal than a two post. Kind of like a fork and a spoon...Ya' use 'em both to put food in your mouth...but some things are easier than one or the other.

 

[cc_rider]

I've decided on a four post for one simple reason: width. Two-post lifts are too wide to fit into a normal two-car garage without giving up a good chunk of width; I'd be surprised if you'd still be able to get two cars in. Four post lifts can fit into the width of half a garage. I've used my buddy's two-post quite a bit and really like the wrenching room, but just can't fit one into my layout. I still want to have the ability to put three cars in the garage.

The other consideration is convenience; if you plan to use the lift to double up your parking, you'll have to fotz with the lift arms whenever you bring a car in or out. Not a big deal if the upper car is a garage queen that rarely moves, but all that fuss for a daily driver would quickly become a PITA. Four-posters are generally drive-on, drive-off.

Short answer: Two-post is better for working on cars, four post is better for storing cars.

c.

 

[OldCarGuy]

I own five 4-post lifts going on 20 years now. Most of the time they are used for storage of antique cars. I have removed a number of straight-eight engines from Packards and Buicks. Replaced rear axles, brakes, transmissions, mufflers, gas tanks, and many front ends. All using 4-post lifts,, raising the car with bottle jacks on a bridge, then placing them with jack stands. Although I’m not in any kind of business and time isn’t an issue, the jobs always get finished. And a heck of a lot faster and easier on my old bones than off the floor.

I now have the luxury of owning a 2-post lift that I purchased earlier this year, that I plan on using for wrenching only. As a hobbyist, if I was to pick between the two as my only lift, I would definitely choose a 4-post. Overall it is the most versatile.