I had to take a rear tire off today cuz it was flat. There are 2 jacks that came with the car originally. I tried several times to use them to lift the car but they seemed to keep walking back from out under the car and the turn crank was close to digging into the body. I was on a flat surface in my garage.

I grabbed a scissor jack from my jeep and used that instead. How do you use these things? They have that bump that fits nicely into the lift point but they didn't seem stable at all. And why are there 2? Are you supposed to use them both at the same time?

The manual doesn't say that.

Thanks!

 

Lubricate the jack.
Open the jack until it almost touches the garage floor while it is correctly located in the jack point. Make sure that there are blocks that won't move under both sides of a tire on the other side of the car, so that the car cannot roll forward or back.
Place the foot on the floor so that it is directly under the jack point on the car. That is, the jack should be as open as it will go and still go between the jack point and the floor, and should be vertical in both fore-and-aft and side-to-side. When you jack the car, it should lift pretty much straight up.

No, you normally get only one jack...

 

I used one once and really did not like how unstable it seemed. I much prefer my alloy racing floor jack

 

I agree with James - As far as I am concerned, the jack is for very cautious emergency usage only...

 

Having been under a 928 once when supported by only the jack (although all 4 wheels were still fitted) I would amplify what Wally said. Extend the jack as far as you can with the locating lug inserted into the jacing point on the car. Keep extending the jack such that the first part of the jack that touches the ground is directly below the centre of the jacking point. (This is what I'ld describe as the HEEL of the jacks foot) keep raising the jack until the TOE of the jack foot is supporting the car - you'll find that this is now vertically below the jacking point. If at this point the centre of contact on the ground and centre of jacking point on the car aren't in a vertical line both side to side and most importantly fore and aft, lower the jack and start again. These alu jacks will crack and fail if there is any significant non vertical load on them especially in the fore and aft direction.

 

+10 on what Wally, James and Jon have said, however, never ever get under a car with only one jack, regardless whether it is a screwed or hydraulic and more especially the emergency jack supplied with the car, even if all wheel are still on the car.

When I jack the car up I use my floor hydraulic jack and then support it with jack stands with chocks under the wheels still on the ground. Many times I will also place the removed wheel under the sill in case something goes wrong.

When the car is supported as described I will then give the car a rock to ensure that it is stable, as i hav experienced cars move when jacked up.

Tails 1990 928S4 Auto

 

I still have the original unused jack and spare tire in my car. Based on this thread and others concerning how effective the spare tire actually is, should I just remove them both, save some weight and get AAA`s ??

 

I work at a university and I once saw a student changing the oil in his BMW with only the front left wheel raised by the car's included jack, in a university parking garage. That could have been a fail on so many levels.

 

That's exactly what I did, except my car was missing the jack anyway.

 

When I would change the oil in my Spitfire I would usually drive it up on the curb with two wheels and then just get under it right there at the curb...no jacking.

As to the stock 928 jack...I can't remember why I was using it...maybe to clean the wheel wells on my '88 right after I got it. But regardless I used it 5 or 6 times I guess and then it pretty much fell apart. The bearings even fell out of the thing! They are truly made to use not more than a few times... EVER!

 

"I still have the original unused jack and spare tire in my car. Based on this thread and others concerning how effective the spare tire actually is, should I just remove them both, save some weight and get AAA`s ?? "

This is another of the questions where answers are based on religion, not facts...

I have kept mine in the 928's, and have used both the jack and spare several times. I don't like waiting beside the road for some yahoo to damage my car getting it on the roll-back, and there are still a lot of no-cell-service areas where I drive. Fifteen minutes of wrestling with and cursing at the spare and the lug nuts, and I'm on my way.

 

How do you get the spare tire to shrink back to its original size and fit back into the well? I can't get mine to fit!

 

I've used the included jack for it's intended purpose, to put on the spare due to a flat.

I used my home floor jack to replace the spare with a new wheel/tire.

I couldn't deflate the spare to refit in the compartment. I tried putting straps around it to squeeze it down but just couldn't get it small enough. I finally took it to a friends that had a vacuum pump and it sucked right down and fit fine. There was a second air fitting that worked better for pulling a vacuum on it.

 

Ah, so I should try a vacuum pump? The PO put HUGE zip-ties around the tire to shrink it back down, unfortunately that made it a bit lumpy now, I should probably inflate it on the car to see whether or not it is even usable still. I cut off the zip ties because I realized I didn't have a knife in the car to cut them off if I ever got stranded.

 

"Very carefully, and hopefully not at all if you can help it. They are just plain worthless. No experiance with the actually 928 jack, but I reconized that gargage right when I saw it from other cars I have owned. "If was stranded on a desert island................, Ok, I might use it if I was stranded on a desert island!