[Bandit1978]

I have a 71 chevelle..need to replace trans mount..350 turbo 350 motor..
I removed the 4 bolts..lifted the tail section up..but I can't remove the mount because there is a metal shaft or peice pointing down..the trans is up against the tunnel..do i have to remove the cross member too?anyway to get it out without removing the cross member?

 

[charbilly2001]

The transmission cross member has exactly 4 nuts and bolts. Thats not a very big mountain to climb Shannon.

 

[Bandit1978]

The transmission cross member has exactly 4 nuts and bolts. Thats not a very big mountain to climb Shannon.

No its not but..it is if the bolts don't come loose..I only wanted to know if the cross member had to come loose to remove the mount..Thank you so much for your helpful insight..

So how high is the mountain?

 

[Dean]

What do you mean "the bolts don't come loose" ?

Ya' gotta make um come loose.

Do you have the bolts going into the transmission out?

 

[70ElkySS]

Shannon - I think the answer to your question is yes, the crossmember will have to come out. Actually, you don't have to take it all the way out, but the bolts will need to come out so you can slide the crossmember back enough to get the mount in. The only other alternative would be to cut the tab off, but I think it's there as a fail-safe, so I wouldn't recommend it.

 

[Bandit1978]

the bolts on one side came loose..but on the other the whole bolt spins..can I get a wrench on top to hold the bolt while I try to loosen the nut?

Yes I have the bolts out that goes into the transmission..

 

[70ElkySS]

Yes, you can get a wrench on the topside. Use a box-end 9/16" and just feel for the bolt head.

 

[Bandit1978]

I fianlly got the crossmember loose..I sprayed some stuff called pb power blaster on them..and let it set for awhile..then they reluctantly came loose..after the cross member was loose the trans mount came out..as I looked at it..the rubber seemed to be swelled..and soft..Ill try to get the new one in this evening..Is there anything else I need to attend to since I am in this area under the car?...

Thanks for all the help..this site is the best!!!

 

[Go69]

If the mount is swollen and/or soft that is a sign that it has been in contact with engine oil, or transmission fluid. Have you checked for leaks under the car? Locate and repair any and all leaks that might be present under the car. Otherwise the fluid will destroy the new mount just like it did the old one.

 

[dreis454]

Spend the extra few bucks & get yourself a mount front energy suspension. You'll be glad you did. 30 bucks through Jegs or Summitt.

 

[Bandit1978]

wonder if I should replace the motor mounts?

 

[Bandit1978]

Anyone?

 

[70ElkySS]

wonder if I should replace the motor mounts?

Hmmm. How about this: If they're bad, replace them, if they're not, don't.

 

[Bandit1978]

Hmmm. How about this: If they're bad, replace them, if they're not, don't.

Hmmmm....Ok thanks for the outstanding advice..

Of course if maybe someone would have added..this is the way to check and see if be chance they are bad..

 

[70ElkySS]

Sorry, Shannon - I was in a ****y mood when I posted that (which is most of the time). I'm no expert, but I think you really need to just look at them and see if the rubber has swelled or has separated from the metal parts. As long as they appear solid and your motor isn't moving around, they're probably OK. On the other hand, if you're not certain, you might want to just put on a new set - it may buy you some cheap peace of mind.

 

[charbilly2001]

Checking for bad motor mounts. Open your hood. Start your engine. Put your gear selector in drive. Firmly press the foot brake. Step on the throttle while watching the engine. If the engine lifts a couple inches on the drivers side as you slowly increase throttle and "thuds" back down when you quickly release the throttle you have a broken drivers side motor mount.

Now put your gear selector in reverse and repeat the brake / throttle on/throttle off quickly. If your engine lifts on the passenger side a couple inches and then "thuds" back down you have a broken right side motor mount.


You have to allow for a small amount of movement because your mounts are a steel/rubber composite so don't be fooled when you see some movement. The real indicator is the engine "thudding" back down onto the broken mount.

If that action is absent then you probably don't have broken mounts. Our SB engines weigh around 450 LBS. when they lift up a couple inches on a side and then are allowed to fall back down suddenly you'll know it. The whole car will shudder.