Trivial question: I use a piece of wood on my floor jack, but jack the car just ahead of the rear tranny cover. Is that a bad idea? ...Saves me time from going from one side to the other and so far no problems.

I have heard two sides to this...Of course. I do not.

Seems like a bad idea to me.

I would be concerned about the stress you are putting on the tranny ears.

I also used to do this regularly, but don't anymore. It does stress the engine and tranny mounts in a way they weren't meant for. Is it likely to cause problems? Probably not. I just don't do it anymore to be safe.

But I've got to admit, it is a quick and easy way to lift the whole rear end at once.

I do it all the time.... But it is probably a bad habit.

I would agree it is better to use the jack point on the side of the car. If you think about it ~1500lbs is probably alot of load for that little mag transmission.

I did buy a trans once from a car that was in an accident and the only thing broke were the ears on the transmission...So obviously they will break.

You've got to think of how much weight you're putting on those ears. Shortcuts are good to find but not when they could cost you money.

I think that if it would hurt something I would have hurt it by now. I've done it so many times on so many 914's and also lifted 911's by the engine cases about a gazillion times. Everyone at every Porsche shop that I worked at jacked up cars like this, too. It doesn't work for VW's or 356's though, it breaks the motor mounts.

So you do what I do- rig up a "U" shape w/ 4x4 blocks, then position the tops of the upright blocks directly on the bolts that support the ears of the tranny. This way the upward force of jacking [off] is being applied to the bottom of the trunk. Two things to make sure of:

1) The length of the uprights is long enough to contact the bolts from the jack in resting position, otherwise you won't get the lift you need to place jackstands.

2) Make sure to secure the uprights to the bottom block w/ nails or screws to prevent unexpected slipping. Learnt that one the hard way.

There's probably still a risk of bending or deforming the trunk pan, but it's safer than putting potentially damaging stress on the ears of the tranny. But so far I've done this multiple times so far w/out any damage.

I go up using the bottom frame jack points and 10 x 10s under the tires. You can do pretty much everything from there.

Which is fine until you need to drop the tranny and the car rolls off the blocks...

i would only do it if you have solid transmission mounts. if you have the stock rubber mounts or 911 sport mounts, you *will* deform the rubber in a way it was never designed to ...
Andy

Thanks for the replies...I do have solid mounts, but I like the idea of blocks to get to the support area...I have extra 4x4 lying around, so I'll give it a try.

i raise one side of the car a few inches with a small jack and then put my big jack centered on the engine support bar. I feel pretty safe lifting from that big piece of iron.

Using the transmission as a jack point seems reeeeeeeeeealy dangerous. Why would anyone take a chance of a seriously messed up transmission in order to save a couple minutes of work. Me thinks these guys have too much money...