[ZeGermanHam]

Hi all. This question is a bit different... I have recently leased my own shop space and purchased a 2-post lift in which to store and work on my '66 GTO and BMW track car. In order to maximize available floor space, I was thinking about putting the GTO up on the lift from about November until March while it isn't being driven much. Is there any risk of causing frame sag by putting a GM A-body up on a lift like that for extended periods?

[grivera]

I’ve had my 64 on the lift for extended periods without issues. If you’re concerned, put underhoist support stands front and back.

[Tom Vaught]

Originally Posted by grivera

I’ve had my 64 on the lift for extended periods without issues. If you’re concerned, put underhoist support stands front and back.

X2.

At my uncle's Pontiac Dealership, he had an old 2 post lift but the posts were at 12:00 and 6:00 vs across from each other.

One morning we arrived and we had the front post had lost oil pressure.
The vehicle was fine as the vehicle "rotated" because the rear post supported the rear axle.

After that we always put Support Stands under any vehicle on that lift is it was left in the air over night.

Support Stands are a very good investment on any lift.

Thinks CAN happen with anything mechanical though.

Tom V.

[gtokid1968]

Please check the concrete under the post!!
I would think it should be a minuim of 4''to 6'' thick! (instructions should say)
If unsure of the concrete, core drill a holle and see what you get.
I have seen people put a large plate of steel down to help spread the weight and get more wedge ancorors in the ground.

[GtoFM]

ZGH, I'm sure you and most others know this, but for those who don't, support the frame ONLY at the points designed by the factory!

[ZeGermanHam]

Originally Posted by GtoFM

ZGH, I'm sure you and most others know this, but for those who don't, support the frame ONLY at the points designed by the factory!

Yep, am familiar with the correct locations, but I appreciate the suggestion nonetheless. When I restored the frame, part of that worked involved bending back the places where previous owners had lifted the car incorrectly.

My primary curiosity is the front section of the frame where the engine sits. I will buy some underhoist supports for general use, but I will likely want to park another car underneath the GTO when it's up in the air. I'm not too worried about the lift lowering on its own, since it has locks to prevent if from doing that. Mostly I was just wondering whether the frame is susceptible to bowing when lifted in the air for a long time.

[Schurkey]

Did your "frame restoration" include new body mounts and hardware?

[Stuart]

It's a debated topic, but some people say that putting a car on a two post lift for extended periods is going to be hard on the suspension bushings since they'll be hanging at full droop.

[Formulajones]

I've had stuff on my 2 post for months at a time with no ill affects at all.
In fact currently, as the engine project gets drug out longer and longer, the vega has been up there since last March so next month it'll be a year. It doesn't even have a frame and no problems at all. Doors still shut perfectly.

[ZeGermanHam]

Originally Posted by Schurkey

Did your "frame restoration" include new body mounts and hardware?

Yes, total frame-off resto for the whole car, which included new body mounts and hardware, and I welded steel reinforcement plates into the frame rails.

Originally Posted by Stuart

It's a debated topic, but some people say that putting a car on a two post lift for extended periods is going to be hard on the suspension bushings since they'll be hanging at full droop.

Very valid point. Fortunately, the suspension bushings shouldn't pose a problem for me, since I have poly and "roto-joint" spherical bushings all around. They won't bind up at full droop like rubber bushings do.

[Sirrotica]

These are my thoughts on the OP's question, when the car is sitting on the wheels, as well as being driven, the longitudinal frame rails are put into a torsional twist due to the control arm mounting points. This twist also stresses the front crossmember trying to twist the ends up, as well as the engine weight trying to push the upper crossmember surface down. All these forces are multiplied when the car is being driven, and road shock multiplies the forces.

When the suspension is hanging on the lift, all the forces are reversed, and the frame rails are trying to twist out at the top. All one has to do is raise a car with a floor jack and see how the upper control arm stress reverses at their pivot point as the wheels drop. Instead of trying to push towards the center of the frame/engine, they tend to pull outwards while hanging.

IMO, I would have zero worries as letting the forces change in the opposite direction as the car is suspended by the lift at the factory lift points. If anything it would slow/reverse the settling of the front crossmember, and frame rails during storage.

If you're worried about the suspension hanging, you can always use some small chain binders to keep the droop to a minimum. At maximum extension the shocks are the limiting link that stops the suspension from dropping as it hangs. To use the chain binders to limit droop, the stress is removed from the shocks, and rubber mounts.

Link to chain binders: https://www.amazon.com/s?k=1%2F4+inc...f=nb_sb_noss_1

4 inches of solid concrete is the minimum thickness of most 2 post auto lifts, you can drill into the concrete with a small diameters concrete drill near the base of the lift to check your thickness. Simply put a piece of tape at 4 inches on the drill before you run it. Some manufacturers only call for 3 inches, so you could mark the drill at 3, and 4 inches.

I have a 12,000 lb 2 post that is suitable for lifting light trucks, the manufacturer required my concrete to be 5 inches minimum due to the larger working limit of the heavier load. I'm in the process of putting in 2 footers, 12 inches thick, 4x4 feet, for the bases of the lift to set on. There will be 16 pieces of rebar tying each new footer to the existing slab. Yes, overkill, but I only want to do it once.

Just my thoughts from being around cars, and lifts for over 50 years, I hope this is helpful...........

[Tom Vaught]

Originally Posted by Sirrotica

I have a 12,000 lb 2 post that is suitable for lifting light trucks, the manufacturer required my concrete to be 5 inches minimum due to the larger working limit of the heavier load. I'm in the process of putting in 2 footers, 12 inches thick, 4x4 feet, for the bases of the lift to set on. There will be 16 pieces of rebar tying each new footer to the existing slab. Yes, overkill, but I only want to do it once.

Just my thoughts from being around cars, and lifts for over 50 years, I hope this is helpful...........

I had the rebar and 4 x 4 feet poured for my two post lift when I had the barn built. Rotary Lift SPO10 which is fine for the Pontiacs.
The "Drivers" are Ford Lease Vehicles.

Do it once and do it right.

Tom V.

[chiefbigb]

When I put my 68 or 70.gtos on my 2 post the nose will come away from the fenders probably 1/4 inch or more. That was very alarming the first time. When put back on the ground they go back in place. If a car was painted with the nose on that could cause a cracking issue. For general repairs and long term storage I think the 4 post drive on is the way

[ZeGermanHam]

Originally Posted by Sirrotica

Just my thoughts from being around cars, and lifts for over 50 years, I hope this is helpful...........

Thank you for your response! It is helpful to think about. As far as the lift goes, it was installed by the previous owner, and I purchased it from him. I'd like to assume he did his homework when installing as far as pad thickness goes, but I will verify.

This is the new space on move-in day yesterday. I will soon be cleaning up, scrubbing some oil stains outof the concrete, doing some painting and drywall work, and I'd also like to get the power supply for the lift off the floor.

[Scarebird]

wow, your Goat barn even has a loft!

Nice find, Karl.

[ZeGermanHam]

Originally Posted by Scarebird

wow, your Goat barn even has a loft!

Nice find, Karl.

Thanks, Mark! Yes, the loft space will be a game changer for me. I currently live in a tiny house with no basement, attic, or garage. I have a small backyard shed that's filled with car stuff, and one of the bedrooms in our house serves as both my home office and storage space for yet more car parts. The loft in my new shop space will be able to hold all that stuff fairly easily, which means clearing out my house and shed finally. The wife and I are both so happy for that.

The other good news is that after having measured the space yesterday, I found that I can store my BMW up against the back wall and still have room to open the bathroom door. I'll have to put it on casters do get it in there, but it won't be hard. This will allow me to store two cars, and three if one is up on the lift and another below it. No plans to get a third toy car right now, though.