Motor/Trans mounts... AGAIN?!?!

[JGrefenstette]

i replaced my motor mounts a few months back. it solved my problem with launch shudder when i let the clutch out. after a few weeks though the problem came back and worse. revers gear was awful. so i got under the truck and re-tighted the mount bolts. this time i put a breaker bar on the wrench and let em have it. this solve the issue almost completely. i could let the clutch out and there was no shudder no hesitation. it just grabbed and was solid. but now it feels like its starting to loosen up again. and i know those bolts arent loosening. and i really dont think i can tighten it much more with out breaking somthing. are my motor mounts bad? ive lifted the hood and done the hold the brake test. they appear ok. but im think it might be that they are bad and by tightening my trans mounts im putting more stress on the motor mounts?



example: 2nd gear @1500 rpms. let off the throttle and i see the shifter move more than a little, step back on the throttle and it moves back again.

revers gear has the same symptoms but much worse



example 2: shut the motor off, and the trans shifter and the 4x4 shifter both move significantly in sync.



what are my options here??? are the rubber transmision mounts just too cushy and dont stabaliz it enough. i got them from dodge. will motor mounts solve this? should i go to polyurithain trans mounts and tighten them aggresively??

 

[JDancoe]

J, For what it's worth- At about 100K on my 92 W-250 I started hearing & feeling a"bumping" and shudder when backing my trailer up a slight hill. Checked the mounts, they seemed ok. Did find the bolts holding the trans mount X-member to the frame slightly loose. Tightened them 1/2 to 3/4 turn, (to whatever the torque spec. is. ) This solved the problem. Shudder is back now, and much worse, at 240+K. Think the mounts are bad now-they're original equipment.
Jack Dancoe

 

[JGrefenstette]

i think we have the same issue. i test my mounts by sticking a crowbar under the trans between it and the cross member, and yank the snot out of it. i tighten the bolts till the crowbar move its hardly at all. when i tightend mine back down i gave em over a dozen full turns. theyre TIGHT

 

[MMiller]

I've had lots of troubles on my truck keeping the trans mounts bolts tight. I've even lost the nut before, but I don't have a shudder like you do, however my truck is just a standard cab.



I pulled the bolts out, got new lock nuts, cleaned the bolts with brake clean, installed new mounts, installed the clean bolts and put red locktight on the nuts, then I run them down as tight as possible with a 1/2" impact wrench.



I think it would be a good investment to put Poly trans mounts, because my new mounts started to show fatigue quicker then the OEM ones did. I'm still running the factory motor mounts for now, I probably should replace them.



Michael

 

[Ncostello]

Are the ANCHOR brand motor mounts from AutoZone any good? Seems like someone mentioned them as being decent.



I'm worried about mine. Under hard acceleration, unloaded, I can hear a distinct "clicking" or "ticking". Almost like the fan blade is nicking something. About that frequency and volume too. But I see no evidence of such.



Low to meduim yeilds no sounds. So I doubt its a u-joint... which I've heard click away before.



I've never checked my trans mount. I'm positive all are original at 200K.

 

[JGrefenstette]

MMiller, yea i think im going to go to the poly and torque the mess out of them. hopefully kill the iritating softness.





Ncostello, it may be worth slipping a crowbar up under the trans and seeing how much you can raise it. i check mine on both sides. so i know how much forward gears will raise it, and mainly reverse, because the different direction of torque usually loosens it up fast.

for the motor mounts - pop the hoop and put it in first or drive, hold the brake and accelerate at the sametime. watch for how much it torques the motor. she shouldnt budge much at all. id repeat it in reverse gear also.

 

[GHarman]

Poly transmission mounts?

Who makes 'em and where can they be purchased? GregH

 

[JGrefenstette]

thats a good question greg. i first heard of them from a guy i know who runs his own shop and is a dodge cummins specialist. i will ask him where i can get them. ill let yall know what he says.

 

[GHarman]

Thanks Bud, I just replaced the motor Mounts with the Anchor's and the transmission mounts with the Quad 4X4 offerings. I am not sure as yet, how long these will last. Had to make a new adaptor plate, no aftermarket's available. Still working on the electrical. GregH

 

[JGrefenstette]

well i just got under the truck yesterday and checked everything over. seems my transmission mounts are as tight as when i last adjusted them. which is what i was affraid of. i think having my trans mounts soo tight put the torque onto the motor mounts, which as i found could def. use replacing. Greg, how tuff is it to replace a set of motor mounts? i just need to hoist the motor a few inches up right?

 

[GHarman]

JGrefenstette, Yes, but be careful of your wiring harness that snakes over the bell housing. It can get pinched at the firewall. There is a sharp edge there. We used a engine hoist and 2 wire rope slings to get the engine up in the air. There is a long convoluted story that goes with this. While working on the clutch replacement, The project snowballed into a nightmare. The short version is that Cummins did the motor mounts for me while replacing the cam and pan gasket. We had access while doing the clutch but at that time decided not to replace them. Changed my mind after Murphy reared his head. GregH

 

[JGrefenstette]

hah, oh yes i sure do remeber reading that short book of all the events that happend to you and the truck during that time. lets hope i have better luck eh? haha