x-member thoughts....

[ryoken]

those that read my build thread know I'm building my trans x-member at the moment.... but i thought i'd throw this thread up to get everyone's opinion..

originally, I was going to have the x-member main section come over and mount by the frame with 4 of these bushings...

I'm still going to do that... but originally i was gonna hard mount the main section at the adapter and upper 205 mount...... but the last couple days i've been considering adding these at the adapter, then doing another urethane mount of some type up at the 205..

your thoughts on "hard mounting" the trans/tcase to the main section, and relying on the bushing mounts out at the edges of the x-member? originally, i was confident in it being a stout setup that would be fine, but i've become concerned about it maybe being too stiff with any torsional load the motor may put on it.... possibilty of cracks, breakage, etc once i get some decent torque from the mill... thus the idea of adding the above mounts..

i like the idea of hard mounting it, simpler, cleaner, stronger, but i'll add the center mounts if i feel it's necessary..

opinions?

 

[tRustyK5]

I'd be inclined to poly mount the tranny and T-case, and the motor. The poly is still quite a bit more rigid than the rubber mounts, but at least has some give. I think hard mounted at the tranny/T-case there would be a hell of a load on the adaptors before it'd even tickle those huge outer mounts. Good chance the adaptors would fail first.

Rene

 

[ryoken]

I'm inclined to agree... tho i'm running poly's up at the motor, I think

hell of a load on the adaptors before it'd even tickle those huge outer mounts

is the perfect description... thanks Rene......

 

[tRustyK5]

I remember this coming up in the Center of Gravity forum a few years ago...and the concensus was whatever mounting system you decided on, the most important part was that the motor, tranny and T-case(s) all used the same material. Mixing and matching poly and rubber was where bad things happened.

Rene

 

[Hogback Fabrication]

I remember this coming up in the Center of Gravity forum a few years ago...and the concensus was whatever mounting system you decided on, the most important part was that the motor, tranny and T-case(s) all used the same material. Mixing and matching poly and rubber was where bad things happened.

Rene

One thing that hasn't been mentioned is leverage. Regardless of material, having the bushings on the ends like that will be much stiffer than poly mounts in the stock location. From the center of rotation to the stock mounts is only what, 4" maybe (i.e. they're 8" apart)? Putting the bushings at the end is probably a foot or so each way.

That being said, I did the same and I'm not worried about it (poly bushings on everything)

 

[ryoken]

Chris, is that the setup you where running in the past, and knowing the use of your truck, run hard, or for that new recent doubler setup you did?

 

[Hogback Fabrication]

Chris, is that the setup you where running in the past, and knowing the use of your truck, run hard, or for that new recent doubler setup you did?

New and not run, in the past I've been good at breaking 465/205 adapters with poly mounts all around in the stock locations

 

[rdn2blazer]

I'd be inclined to poly mount the tranny and T-case, and the motor. The poly is still quite a bit more rigid than the rubber mounts, but at least has some give. I think hard mounted at the tranny/T-case there would be a hell of a load on the adaptors before it'd even tickle those huge outer mounts. Good chance the adaptors would fail first.

Rene

Exactly what Rene said. Very nice option. I'm going to do the same thing when I get to that point.

 

[76zimmer]

I agree with the central mounting of the trans/t/c and let the engine mounts handle the twist. It seems the mounting of the t/c close to the frame would lend itself to snap the trans case, or another aluminum component (sure won't be that 205 you got). I think the stiffer you can make the frame against torsional twist would be an advantage also.

 

[ryoken]

I'm going with those energy suspension mounts I posted above.... i figure it certainly wont hurt, and nows the time to do it... not re-engineering it if/when i break a bellhousing, etc...

kinda screwed me up this weekend tho.. cuz i wanna wait till i get em to go any further on the x-member... Summit will have em to me for next weekend... needed to do an order with them anyway...

no biggie, obviously i have tons to do... i was just final mounting the bumper and winch. have some other projects in mind for the next 2 days too...