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- - No tranny mount on my TH400? 70' c10 (https://67-72chevytrucks.com/vboard/showthread.php?t=697303)

Re: No tranny mount on my TH400? 70' c10

From what I gather reading and looking at Google images, the transmission should have a mount at the crossmember and the tail shaft. Does it matter when I'm getting parts that I have a TH400 instead of TH350

Re: No tranny mount on my TH400? 70' c10

That is the correct mount, and i am not sure, but i believe it does not matter if you have a t350 or t400. I do recommend, however, that you buy a polyurethane mount, like one from energy-suspension, they last longer, and in my opinion are much better.

Re: No tranny mount on my TH400? 70' c10

So was the engine leaning back against the firewall? This is wild!

Re: No tranny mount on my TH400? 70' c10

Quote:

Originally Posted by gvnick (Post 7488909)

So was the engine leaning back against the firewall? This is wild!

Oddly enough no lol there is a crossmember there but it's not bolted to the transmission.

Re: No tranny mount on my TH400? 70' c10

Is the trans mount broken or just missing the bolts?

When you were getting on it before you tore it down, did it vibrate or make a thumping noise like the trans was hitting the body underneath?

Were there vibrations on acceleration or deceleration?

For me, as far as the trans mount, I would not go to a urethane mount unless you go with the same urethane type motor mounts. The engine and trans needs to be able to move with each other. If you have a urethane trans mount (stiff) and rubber motor mounts (not as stiff) you take a chance on cracking the trans tail shaft housing.

Re: No tranny mount on my TH400? 70' c10

Quote:

Originally Posted by tcrist (Post 7488996)

For me, as far as the trans mount, I would not go to a urethane mount unless you go with the same urethane type motor mounts. The engine and trans needs to be able to move with each other. If you have a urethane trans mount (stiff) and rubber motor mounts (not as stiff) you take a chance on cracking the trans tail shaft housing.

You are exactly correct, i was just assuming that he would change the motor mounts, sense they had all of that unstrung weight on them

Re: No tranny mount on my TH400? 70' c10

Quote:

Originally Posted by tcrist (Post 7488996)

There's nothing attaching the transmission to the crossmember that IS there, and it's too far away from the transmission to be bolted to it. That's why I'm thinking it's not the correct crossmember. I'm ordering some motor mounts and transmission mount from Energy Suspension, and I have a crossmember lined up as well.

There was a bad vibration any time I went over 55-60. And no thumping except for when I would manually shift and hold a gear at high RPM's and then floor it (like racing from a roll) and on major deceleration.