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Old 02-05-2013, 02:01 AM   #1
hotrod1
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Need Opinion-Transmission mounts-help!

The delima:

Option:
A) Use a standard transmission urethane (in picture 1) mount which I rather not use because my motor and trans already sit low in the frame and the cross member will hang too low as well.

B) Use urethane bushings (picture 2) in the ends of the cross member (picture 3) while hard bolting the cross member to the trans. preferred option for me. Am I going to run into problems doing it this way like trans tailpiece cracking or are these bushings good enough? By the way, the engine mounts have the same bushings on them for mounting the engine to the frame.

I want to keep the cross member as high as possible but if I use option 1, that large mount will force me to mount the cross member low because it is so tall.


What is you opinion and why?

Thanks in advance!!!!
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Old 02-05-2013, 09:36 AM   #2
Speedbumpauto
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Re: Need Opinion-Transmission mounts-help!

Hard to visualize alternatives without seeing the problem, at least for me, but I see no problem using your option 2. I can't see any cracking or other problems using that mount. It looks pretty slick if you have to buy a crossmember.
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Old 02-05-2013, 06:07 PM   #3
_Ogre
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Re: Need Opinion-Transmission mounts-help!

i'm having problems visualizing your dilemma too
the lowest point on our trucks is the rocker panels
not sure what year your truck is, but on a 55-59 the frame is 6'' higher than the rockers
it's hard to imagine installing the motor so low that the trans x-member would be a problem
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Old 02-12-2013, 06:49 PM   #4
skymangs
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Re: Need Opinion-Transmission mounts-help!

I would recommend against the outside bushings and hard mounting the tailshaft. I did this with my non Chevy rock crawler, and cracked the tailshaft housing the second time out. granted you may not have the multiplied torque that I did.

If you want to use bushings on the crossmember mounts, I would put some thin poly "donuts" under the trans as well. Just to be safe. I did this on my crawler, and never had another issue. You can get a whole package of them (6 or 8 I believe) for like $10-15 at Oreillys.
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Old 02-12-2013, 10:28 PM   #5
hotrod1
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Re: Need Opinion-Transmission mounts-help!

Hey Skymangs:

Thanks for the info. Do you have any pictures of what you did and the final product?
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Old 02-12-2013, 11:11 PM   #6
skymangs
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Re: Need Opinion-Transmission mounts-help!

but of course. Mine had to support two transfer cases and clear the front driveshaft, so yours would be much less complicated.

Pics below. I don't have any of the poly "donuts". If I remember correctly I bought them from either 4 wheel parts or Oreillys. been awhile. They are just like Polyeurothane washers. Maybe 3/4" thick, and 2" in diameter. Just put them between the trans and the mount when you bolt it down. That will give it just a little wiggle room.

Hope this helps
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Old 02-12-2013, 11:27 PM   #7
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Re: Need Opinion-Transmission mounts-help!

The issue (as it was explained to me) with solid mounting your trans and bushing mounting the crossmember is that all your torque pivots down the centerline of your driveline. The bushings on the framrails just don't move far enough, resulting in breakage at the fulcrum (transmission tailshaft housing).
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Old 02-12-2013, 11:29 PM   #8
hotrod1
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Re: Need Opinion-Transmission mounts-help!

Thanks for the pics and explanation. I appreciate it.
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