Heavy vibration/rattle felt through shifter

[04OWwhipple]

I did a pull on my new setup up through 4th gear this weekend. By the top of 4th I had a super heavy vibration through the shifter and a loud rattling noise also emanating from the shifter.

This is the original T56 with a steeda Tri-Ax shifter and a Mcleod RXT clutch. I recently rebuilt the engine and installed poly motor mounts. I don't remember this noise ever being present even slightly before. Do the poly mounts raise the engine enough to throw off driveline angles or anything? Anybody else experienced this?

 

[CobraBob]

No vibration/rattle with "normal" lower RPM shifting after that occurance?

 

[04OWwhipple]

No vibration/rattle with "normal" lower RPM shifting after that occurance?

It always has had the low RPM T56 growl ever since I bought the car. That occurs rattle when RPMs are 1800 or less. But I don't remember ever having this intense of a noise when doing a pull, let alone the vibration. I don't feel anything abnormal at lower RPMs compared to before my engine rebuild

I actually just placed an order for you shifter gaskets about 15 min ago Bob. haha. But I starting to wonder if the shifter cup came out of my trans during the rebuild as I did have the shifter off of the trnasmission twice during that process.

 

[01yellercobra]

Get under the car and made sure nothing is touching that shouldn't be. Like the exhaust and stuff. Also make sure the driveshaft bolts are tight.

 

[04OWwhipple]

Get under the car and made sure nothing is touching that shouldn't be. Like the exhaust and stuff. Also make sure the driveshaft bolts are tight.

I'll recheck the torque on the bolts but they should be tight as I just had the u-joints replaced and driveshaft rebalanced as well. I didn't think about it hitting the exhaust though. I'll have to check that out. I don't really feel any vibration in the car/seat bottom. but damn the shifter vibrates likes a banshee

 

[01yellercobra]

I'll recheck the torque on the bolts but they should be tight as I just had the u-joints replaced and driveshaft rebalanced as well. I didn't think about it hitting the exhaust though. I'll have to check that out. I don't really feel any vibration in the car/seat bottom. but damn the shifter vibrates likes a banshee

I had installed the driveshaft in my 01 and a few days later had a vibration show up. I put it off for a bit. When I got under the bolts had backed out about halfway. Oops.

 

[CobraBob]

It always has had the low RPM T56 growl ever since I bought the car. That occurs rattle when RPMs are 1800 or less. But I don't remember ever having this intense of a noise when doing a pull, let alone the vibration. I don't feel anything abnormal at lower RPMs compared to before my engine rebuild

I actually just placed an order for you shifter gaskets about 15 min ago Bob. haha. But I starting to wonder if the shifter cup came out of my trans during the rebuild as I did have the shifter off of the trnasmission twice during that process.

Yep, I saw the order a couple of hours ago, Julian. Thanks for the order. It will ship out tomorrow. You'll receive an email with tracking info at that time.

I think the vibration and noise is directly related to the poly motor mounts. Increased noise, vibration and harshness is common with poly mounts. Here's a good read for you, and after browsing this thread you might agree.
https://www.svtperformance.com/threads/solid-motor-mounts-ftl.583821/

 

[04OWwhipple]

So if it's turned off in my tune is that charcoal canister or purge thing even doing their jobs? I only ask because the hot water heater is in the garage and am wondering if fumes would ignite

Yep, I saw the order a couple of hours ago, Julian. Thanks for the order. It will ship out tomorrow. You'll receive an email with tracking info at that time.

I think the vibration and noise is directly related to the poly motor mounts. Increased noise, vibration and harshness is common with poly mounts. Here's a good read for you, and after browsing this thread you might agree.
https://www.svtperformance.com/threads/solid-motor-mounts-ftl.583821/

Perfect, I will look for them in the mail. I figured it's a good time to put your gaskets in when I have the shifter out making sure that cup is in there.

I'm sure poly mounts do transfer more vibration but I think that is is more dependent on vehicle speed over engine RPM. I suppose it could be engine vibration that I haven't noticed during 3rd gear pulls as that gear goes through RPM much quicker. I only have the engine mounts as poly. The trans mount is still rubber.

 

[CobraBob]

I was worth a look see. I have to agree that the level of vibration you're describing would seem to be in excess of what that thread is talk about.

 

[04OWwhipple]

Well even with new gaskets I still have a hefty vibration present. I inspected under the car and don't see anywhere that the driveshaft is contacting anything. I'm starting to run out of ideas to check at this point. I can't imagine something when bad inside the transmission from the engine rebuild. I started to think about the pilot bearing but would imagine I would have other signs if that were bad.

Has anybody else had any experiences with a bad pilot bearing and what symptoms did it give you if so?

 

[BlckBox04]

Did you actually take the trans out of the car or just the motor

 

[04OWwhipple]

Did you actually take the trans out of the car or just the motor

Both. I removed the engine and trans together from the car. Then separated them once out.

 

[BlckBox04]

I know someone above already mentioned it but is it still possible drive shaft has something to do with it

 

[04OWwhipple]

Anything is still possible certainly. I already had the driveshaft u joints replaced and balanced afterwards and it seemed to check out fine on the balancer but they could have done it wrong I suppose. I just crossed that off my list after having that done but I may take it out and take it somewhere else if it comes down to it.

 

[BlckBox04]

maybe the flywheel or clutch itself

 

[04OWwhipple]

maybe the flywheel or clutch itself

I had thought this as well, I started to shy away from that idea as it's still the same clutch and flywheel setup that was on the car before the rebuild. Im gonna try swapping my 15 inch wheels/hoosiers on it this weekend at the track and see if I somehow get lucky and have a random tire vibration. I don;t really remember my seat shaking or anything like that but at 140 I'm kinda of focused on other things. I haven't done many pulls to that speed so I only have limited data on the situation thus far. Hopefully with track time I can focus more on the problem in that environment.

 

[04OWwhipple]

UPDATE: Measured driveline angles last night and found that them to be quite a bit out of spec so I believe that may be the culprit. I need to resolve the angles and retest to see how it goes. I installed poly motor mounts when I installed the rebuilt engine and I believe this raised the engine quite a bit. Also, when I was under the car last night it does not appear that the engine mount studs were sitting down at the bottom of the slots in the k-member which would be a problem. More to come once I have more time to spend on it.

 

[BlckBox04]

pinion angles will definitely have something to do with that. the geometry is all out of wack

 

[04OWwhipple]

pinion angles will definitely have something to do with that. the geometry is all out of wack

Definitely. It's seems to be pretty bad. Spec is no more than 2 degrees difference and ideally they should cancel each. I show 2.5 degrees difference so at 135 mph that would definitely do it I feel like.


This is what I had measured last night:

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