Question: About how long/difficult to replace trans mounts

Tidybuoy · 03-25-2014, 10:33 PM

I'm just wondering how difficult it is to replace the transmission mounts - these are the two mounts that are identical to the engine mounts. I'm hoping to get this done this weekend and want to get a general idea of what I should expect.

Caledonian · Caledonian's Garage

The time it takes you to jack up car and put stands underneath.

And assuming your nuts and bolts are not seized and you have decent tools, around 20min to change them over.

I mentioned the job in my thread, Old 911 with new owner but I'm sure there will be others on here with more detail.

If you have not already done them, i would do your engine mounts at the same time.

JJ 911SC · JJ 911SC's Garage

Less than one hour.

You'll need to shore up the transmission, removed the 2 - 12mm bolts/washers then removed the 4 nuts/washers that hold the cross bar to the transmission, remove & replace the mounts on the bench. Leave the bolts/nuts holding the mounts to the bar loose so that they can move around for proper line-up. When all the nuts are hand tight start torquing them (cross bar, 12mm and mount bolts last).

Have Fun

SiberianDVM · SiberianDVM's Garage

Like they said. About the easiest job I ever did on the 911.

tobluforu · tobluforu's Garage

You have to take care not to cross thread when installing, besides that, pretty easy.

McLaren-TAG · McLaren-TAG's Garage

About as long as it will take you to run out and do the groceries.

CCM911 · 03-26-2014, 05:29 AM

It would be a good idea to do all four mounts while you are at it. Not muxch more expensive or time consuming.

$ Short · $ Short's Garage

I know my 88 w G50 took a little longer than my brothers 915. Both were very doable and outcome was worth the effort.
Kurt

Flojo · Flojo's Garage

probably one of the absolutely most easiest parts to change.
you can do it lying on the floor with a little lift at back midsize of the engine (secure with jacks!!).
you'll need an other lift to secure the tranny in position BEFORE unwinding the two centerbolts and the 2x 2 bolts from each mount.
pull em out and stuff the new in. about done!

but while you're in there: refurbish that bridge (at best: bead blast and powdercoat)
4 srews fixing the bridge to the tranny.

ClickClickBoom · ClickClickBoom's Garage

Make sure you torque to factory specs, and recheck after a hundred miles or so.

JAR0023 · JAR0023's Garage

Quote:

Originally Posted by tobluforu

You have to take care not to cross thread when installing, besides that, pretty easy.

Agree with the others. Not hard at all. Loosen the bolts that hold the trans to the mount and you can move it around enough lineup the main mount bolts. Once the car was on jack stands I used a small bottle jack and a block of wood to support the front of the transaxle while I swapped in the new mounts. -J

wolds · wolds's Garage

Might want to replace your ground strap while you're at it. Warren

Rich Gas · 03-26-2014, 02:54 PM

I don't know if this was mentioned above, but be very careful around the throttle linkage by the crossmember. I just replaced mine today and it's not that easy using two jack stands with the wheels on. Probably made it harder on myself. The mounts I replaced were already sports. Interesting. Checked the Bentley and I was missing the lock washer. I just replaced them how I found them at 58ftlb. Might go back later and add the washer.

Hope I didn't bend the linkage too bad.

Rich

LEAKYSEALS951 · 03-26-2014, 03:49 PM

Easy project, but be careful:
+1 on being careful not to cross thread and +1 for loosening the four bolts that attach the crossmember to the transmission when reinstalling! Tighten those last. I had my front transmission mount off recently only to find the previous owner had pretty much stripped out the inside threads.

When you go to reinstall it, think of the internal threads as super delicate. Examine your current bolts for stripped thread debri. Don't use power tools. It is way too easy to get lazy and use the pointed transmission mount bolt heads to try to line the entire engine/transmission up. I think that's how the po stripped mine.
There are fixes for this, but you don't want to deal with this if you don't need to.

Tidybuoy · 03-26-2014, 05:01 PM

Thanks everyone! I'm glad to hear that this should be easy. I only bought the two mounts and will get the engine mounts done at a later time. I needed $5 to get the free shipping and so I spent $60 on a pair of mounts. I figured I would do the transmission mounts since the existing ones are old and greasy.