TR2/3/3A Proper Use of Jack Stands on Rear of TR3B

[af3683]

Hello,
I'm looking to remove the rear wire wheels on my TR3B in order to replace the tire. I would appreciate any help on the proper way to jack up the rear of the car and place the car on jack stands. I assume the sequence is as follows:

- Place the car in 1st or 2nd gear. Note my emergency brake is not the best.
- Place the jack under the differential and jack the car up.
- Place the jack stands underneath the left and right frame members just behind each wheel near the brakes.
- Lower the car onto the jack stands.
- Keep the jack underneath the differential as added precaution.
- Use a hammer and block of wood to remove the 2 rear knock offs.

Also, I assume that it is a good idea to put something like an old inner tube on top of the jack stands as well as on top of the jack so one doesn't scratch the frame or differential.

I would appreciate any comments or suggestions. Thank you.

Art

 

[NutmegCT]

Art - first thing I do whenever jacking *any* car:

Block the wheels opposite the end you're lifting, so there's no possibility of the car rolling "away" from raised end.

I put a piece of split firewood in *front* of each front tire if lifting the rear, or vice versa.

Also, it's easier to remove the wheels if you slightly loosen the lugs/knockoffs *before* you raise the car.

Tom

 

[TR3driver]

Definitely block the other end, but IMO you should block both sides. While it's on the jack, it can roll either way. I use 2x4 scraps leftover from a remodeling project.

Don't set the brake or leave it in gear, IMO.

Personally, I try to avoid jacking under the diff. Too easy to damage the seal between the cover & the pumpkin, or beat up the drain plug. Plus it puts an unusual strain on the tubes, which aren't always as strong as they look. Instead, on the TR3, I jack under the rear cross tube. Also makes it easier to judge how high to jack it up, don't go any higher than necessary.

Take part of the weight on the jack, then loosen the knockoffs. A lead-faced hammer will work much better than a block of wood. Or some people cut out a "wrench" from 3/4" plywood that fits over the knockoff.

When you are done, snug up the knockoffs, then set the car down for the final tightening. Be sure the clean the splines and re-coat with anti-seize while you've got the wheels off.

 

[af3683]

Randall,

Can you explain further what you mean by jacking the TR3 up under the "rear cross tube." Thank you.

Art

 

[angelfj1]

Art: Do you have an owner's manual or a "Bentley" manual. Here is a clip of the chassis intended to show lubrication points, but it is also serves as a good reference for potential jacking points. Rear cross member indicated by red arrow.

good luck

 

[Member 10617]

Art,

You have received good guidance and advice from the experts. I'll add my two cents worth based on my experience.

Yes, indeed, don't jack up your car with the jack under the differential. Use the rear cross tube. But be careful. The tube, being a tube, is round. And as you raise the car, sometimes the jack moves... and it can slip off the rear cross tube. I had this happen with a scissors jack (never use a scissors jack for this kind of work!) and the car came down, fortunately not with me under it (I never go under a car unless jack stands are in place).

I always block both front wheels when I am lifting the rear end, as the car can roll forward. And as you jack up the car, it's a good idea to check the front blocks as you raise the rear end because the car may have pulled back from them a bit.

 

[af3683]

Thank you all very much The diagram really helped a lot. I just went out to the garage to check for the rear cross tube. The rear cross tube is a bit deceiving. When you first look at it it really does not appear to be sturdy enough to lift the entire rear of the car. However, I did try it and everything worked fine. Also, I put the jack right in the middle of the cross tube where it bulges out a bit. I assume that there is nothing wrong with jacking the entire rear of the car up as opposed to jacking up one rear side at a time.

Art

 

[Member 10617]

Art.

There's nothing wrong with jacking up the entire rear of the car as long as you follow all the safety precautions mentioned earlier.

 

[af3683]

Randell,

Regarding keeping the car in gear when you jack it up, it seems like it would be a good precautionary measure to keep it from rolling. Is it your opinion that this can damage the transmission?

Thanks,
Art

 

[TR3driver]

Well, the main thing is that, once the rear wheels are off the ground, having it in gear (or the e-brake set) is no longer holding the car from rolling. It can be a very unpleasant moment to discover that it "wants" to roll, regardless of whether your jack rolls with it or tips over. So IMO it is better to rely on wheel chocks at the other end.

I also prefer to not beat against the gears, but I doubt you would ever actually damage anything that way.