Vibrations after motor mount replacement

[dbrannon79]

They looked the same when I pulled the old ones out and compared them. Both engine mounts were the same part number

I do remember when I installed the tranny mount the cross member bolt hole is slotted front to back and the stud on the mount that sticks through was to the back of the slot for both the old and the new mount

I wonder if I were to loosen the nit on the tranny mount use the jack to take the weight off and a heavy strap to try pulling the motor forwards will help

 

[Will L.]

Maybe

 

[dbrannon79]

Hopefully the weather will be in my favor this weekend I’ll pull the inner fender to take a good look at the down pipe too. It could be rubbing against something. It was awfully close to the manifold where I couldn’t fit my fingers behind it before. There’s a chance it moved and the vibration is resonating down the pipe. I know the whole exhaust system is ridged all the way through

most exhaust systems I’ve seen all have some sway or give in them when you tug on the tail pipe. Mine has no give to it anywhere

 

[dbrannon79]

Well I’ve started on it early. Got the inner fender pulled didn’t see anything unusual but the down pipe is under some stress. The turbo flange looked crooked but since the whole system is ridged I’m going fourth with a section of flex pipe

As soon as I pulled the down pipe away from the intermediate pipe the intermediate pipe and further back now has some sway like I feel it should be

 

[dbrannon79]

I’ve got 18 inches of flex pipe to play with. I’m thinking about cutting the down pipe just after the elbow and right before it comes through the frame giving me a little slide in and out room plus I’ll be able to tweak the flange a bit so I can have at least a fingers width between the pipe and the manifold where the #6 glow plug wire is

 

[dbrannon79]

Well got it in. All clamped down and secure. I can slip my fingers behind the pipe at the #6 glow plug wire and shaped it so there’s plenty of clearance around the frame and the engine so I’m happy that part was a success. I’ll take some photos in the morning but I did get a better look at the motor mount on the passenger side and it is pulled back where the top bracket that’s bolted to the block seems to be touching the clamshell of the mount itself. So my plan in the morning is to loosen the tranny mount, jack up on the tranny pan and attach a heavy strap or the come a long to the front of the engine to try sliding it forward a tad.

 

[ak diesel driver]

https://www.summitracing.com/parts/sum-643030?seid=srese1&gclid=EAIaIQobChMI7seh_ZzO8wIV-A-tBh0S6w2iEAQYASABEgKU8_D_BwE

this is what you should be using, the other won't last very long

 

[dbrannon79]

That’s what I was thinking

 

[dbrannon79]

Here’s a couple photos of the down pipe with the flex installed. Plus a quick pic of my trans mount in the crossmember that’s slotted. The stud is all the way back. Loosened it and the driveshaft center bearing since it’s also slotted in the crossmember. Time to try wenching the engine forward a tad.

 

[dbrannon79]

How does this look? Slot on crossmember for tranny mount is centered. Still have straps pulling pressure on the engine but mounts look pulled more forward now. Plus look at my rad fan in the shroud now with just that little bit of tugging I did.

first photo is the passenger side mount. Next two is the driver’s side then the tranny mount and the fan.

passenger side


drivers side front of mount


Driver’s side rear of mount


tranny



fan shroud alignment

 

[ak diesel driver]

Looks much better

 

[dbrannon79]

Well I pulled the straps off and cranked her up. I have to say it’s better but still has a little vibration. At least this time it didn’t vibrate my chicken cup of iced tea off the battery like it did before lol

 

[dbrannon79]

I suppose I’ll live with it for now. I did talk to the manager at AAP while I was there getting the flex pipe and clamps about the issue and he told me he was having the same thing with his car. Used the same brand mounts and his keys and anything loose in his car would rattle at idle. Unless I get to where I can’t stand it, When I find and actually do an engine replacement I’ll install GM mounts

btw I’m posting an updated video for the blow by on the other blow by thread. Tell me if it’s getting worse!

 

[dbrannon79]

Did a little looking on my truck today and discovered something. it might not be contributing to any vibrations, but I didn't think it was right. I found that the side steps are welded to the frame and have a welded flat that goes up and bolts directly to the cab below the doors. I thought this limits the give and flex on the cab to frame. I unbolted them and used a jack to lift slightly on the cab. cut some rubber spacers out of some old rubber mudflaps I got from work. squeezed them between the cab and the flat bar where they were bolted. I'm not sure if I should reinstall the bolts and just not tighten them down all the way or just leave the bolts out. they don't have much give to them when steeping on them without them bolted to the cab.