View Full Version : gearshift moves up and down under/off power in 1/2 and a bit less in 3rd

09-24-2010, 07:31 PM
topic says it all. i also have a very awful rattling underneath the car while going down insanely bumpy dirt roads (thank you, bulloch county, for not giving a damn about dirt roads).

what i want to know is basically an FAQ about transmission mounts, and how and or if this is related to my problem. just got my car out of a shop to get the heads redone after a massive overheating issue.

i called the local transmission shop, spent about a half a minute on the phone. asked the guy that answered 'i want a price quote, transmission mounts on a 3.8 v6 manual firebird', he says 'yup i done one of dem before, had to special order parts, $900". i said thanks and hung up on him. that has to be a joke, i just had my heads totally machined and valves done for 1200, there's no way in hell replacing transmission mounts can be this expensive!

so somebody please break this down for me. i'm planning to go to the muffler shop and get them to put it on a lift and see if they find anything loose before going elsewhere, as i know the guys at that shop are halfway honest.

09-24-2010, 08:08 PM
A transmission mount is very easy to replace and should not run anymore than 35 for the part if even that (haven't bought one in awhile). Its not labor intensive...so you did the right thing by hanging up. Sounds like he threw out a number to see if you would bite or not.....

09-24-2010, 10:21 PM
well i'm a motorcycle mechanic, not a car mechanic, but i know damn well anything related to changing mounts can't cost anywhere near that much even if they had to drop the tranny or hell even the motor as well.

i haven't looked at any diagrams from a service manual, can you guys show me some fiches by chance? i'd like to know exactly what i'm looking at and what needs to be done.

09-24-2010, 10:26 PM
Sounds like a trans mount. It's fairly easy to replace.
Support the trans. Remove 4 bolts and a nut and the crossmember
is out. Then I think there's 2 that hold the mount to the trans.

09-24-2010, 11:27 PM
That's what it is. Done mine twice already. $35 and about an hour.

09-24-2010, 11:41 PM
thanks guys. so tell me why would a supposed 'well reputed shop' quote me like this? i know it's all good to fool the unknowing but that's a pretty penny compared to an overstatement...

i'll be doing some more homework in the next few days.

now let me know this, what's the long term repercussions of not getting this fixed? if any?

09-25-2010, 03:41 AM
Keep an eye out for that midshaft support bearing. That part went to crap on every v6 F-body I ever had, they can shake n make all kinds of noise. Might want to consider a 1 piece DS swap in the future.

09-25-2010, 10:40 AM
now let me know this, what's the long term repercussions of not getting this fixed? if any?

If the shifter is moving, that means the trans is moving. If the
trans is moving, that means the torque arm is moving. If the
torque arm is moving, that means the rear is rotating which
puts unnecessary stress on the u joints. Also puts more
stress on the motor mounts, and I'm sure there's more.

It would be stupid to not replace a $35 part if thats your problem.
And I mean that in the nicest way possible. :lol:

09-25-2010, 10:45 AM
thanks guys. so tell me why would a supposed 'well reputed shop' quote me like this?

I did my second one, but because I live in an apartment, I actually had Firestone Autocare do my first one, and it was only $90. Are you sure he said 900 and not 90?

09-25-2010, 09:45 PM
yeah dude totally said 900. i'll be looking elsewhere. thanks guys.

how hard is it to get to the midshaft support bearing and replace it?

09-26-2010, 12:54 AM
Your profile says you have an 03 firebird......
So what year is it really? The earlier v6's are the ones
with the 2 piece driveshaft.

09-26-2010, 12:48 PM
I would look into a one piece steel or aluminum driveshaft (assuming you do acutally have the 2 piece). It would probably actually take you less time to replace the whole driveshaft then that mid bearing. plus its lighter either way. aluminum ds can be had for around 100 bucks and a steel one even cheaper. well worth the money. You can go ahead and replace the ujoints at that time (that may or may not have been hurt by your busted trans mount)

10-15-2010, 02:52 PM
i guess it's been a while since i joined because it also said i still had the 3.42 LSD....which has been toast since a year ago.

i probably thought of my bike's year when i entered that. bike is an '03, car is an '02. sorry for the confusion.

anyway, i got the mount replaced for dirt cheap. looked under the car when the mechanic had it on the lift and yeah there pretty much was no mount left.

10-15-2010, 05:19 PM
Sweet dude glad you got it fixed.... without a lot of dough lol.