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Poly trans mount options?

85 Jimmy

Sheepdog
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What are the options we have for a poly transmission mount for a 700r4?

Last night on my way home I destroyed ANOTHER energy suspension poly mount... The metal that is embedded in the polyurethane, that the cross member bolts to, pulled out of the polyurethane. This has happened to me before with an energy suspension mount.
 
You need to fix your motor mounts.

That would be my first guess as well, if the motor mounts are loose it can destroy a tranny mount, or worse, crack a tranny case. I used the poly inserts for the stock clam shells with good luck for a while now.
 
I'm running Kert's "Competition poly motor mounts". They are tight and have no play.
 
Are you using a 2WD trans mount in a 4WD application or something or what exactly is it? How often does this happen?
 
I'm using a 4wd mount. It's a energy suspension mount for a 700r4. The first one lasted about a month, then I got it replaced under warranty. This one has lasted a few years, but, the truck hasn't seen a lot of driving over the last few years.
 
Is it a single center mount or the dual seperate mounts that sandwich the crossmember?
 
Here's the mount.

FB100197-2CD6-44BA-82B5-A7D91231EEC6_zpskaterctr.jpg


I know I didn't have to pull the t-case and adapter to get to the mount. I was already planning to reseal my leaking t-case and adapter, I just noticed the mount last night when it felt like my transmission was hitting my trans tunnel.
 
Something isnt right with this picture. Those competition style mounts should offer almost no movement in the drivetrain, and certainly not enough to warrant breaking transmission mounts.
 
Yeah, this sucks and smells of something else going wrong.

I've got Kerts mounts and run a stock trans mount, same adapter etc as yours. Lots of time and abuse so far. You could try making a spacer and running those small hockey puck style pads, but they don't offer much movement. I'd worry about breaking something. How's your frame and crossmember?
 
Try a rubber mount for ****s a giggles. But my money is issue somewhere else. Perhaps time to consider welding the rivoted crossmembers on the truck because Im leaning towards frame twist.
 
When you install the crossmember and mount, do the parts line up easily or could it be in a bind?
 
Yeah, this sucks and smells of something else going wrong.

I've got Kerts mounts and run a stock trans mount, same adapter etc as yours. Lots of time and abuse so far. You could try making a spacer and running those small hockey puck style pads, but they don't offer much movement. I'd worry about breaking something. How's your frame and crossmember?

As far as I know my frame is fine. It is a little bent where the trans crossmember bolts to the frame, but other then that it's fine. The crossmember was also bent where it mounts to the frame. But I flattened it back out and welded plate in the crossmember to strengthen it.

Try a rubber mount for ****s a giggles. But my money is issue somewhere else. Perhaps time to consider welding the rivoted crossmembers on the truck because Im leaning towards frame twist.

Which crossmember would you be talking about? When I go doubler I plan making a new crossmember for the trans/doubler. I've posted this picture before, but I plan to build one similar to this picture that I took off pirate.

1399496755_zps1fc6c7bd.jpg
 
Engine cross member and the rear crossmember . mostly the engine cross member though.

When you make a flat belly like that make some brackets to triangulate the top of the frame rail too.
 
Engine cross member and the rear crossmember . mostly the engine cross member though.

When you make a flat belly like that make some brackets to triangulate the top of the frame rail too.

I have the ORD engine crossmember in, and I recently went over the bolts that hold it in to make sure they were tight, they were.
 
I wonder, could the mount being soaked in ATF cause the polyurethane to swell, causing the metal to be able to be pulled from the urethane? I've had a leak at the t-case adapter for a few years now (the reason I really pulled everything), and when it leaks, it's leaking all over the mount. :dunno:
 
Has anything contacted your transfer case while wheeling, causing it to pull the mount apart? Because the weight of the vehicle pushing up on the transfer case could easily rip that mount apart. This could also happen if the rear driveshaft was too long.

I used the older style factory mount (mine was factory on 83) that sandwiches the frame, then it can't pull the mount apart because it is on both sides of the crossmember.
 
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