Driveline Vibes

I am having problems with my 73 cj5. I changed the t14 to a SM 465 transmission. Of course that made the drivetrain longer, and the rear driveshaft shorter. I have been reading the driveline thread by 70cj5134f.
My tcase is tilted down at 3 1/2-4* and my rear pinion was tilted up at 10*. With this setup, I had some vibration. So I tried removing the 6* shims from the rear spring pads. I now have 3 1/2-4* of pinion angle. This is factory angle. My crossmember is spaced down 1 1/2 in from frame.
The vibration is even worse. I have messaged mcruff about some 8* shims, but is that the way to go?
I am running a new Tom Woods driveshaft with the double cardan joint and special yoke.
The driveshaft is 16 3/4 in long.




Here is a pic of my crossmember and tcase mount. That is the Novak adapter and mount. What I am wondering is, shouldn't there also be a mount on the rt side of the tcase to stop rotational force? Didn't come with one.
Any help appreciated.
Tim

 

UH OH I should have put this in the intermediate forum. Sorry mods. I will do better next time.

 

You def need a tcase mount to get a handle on the torque. Using a protractor your pinion and tcase output need to be fairly close. Shim rear/ transmount accordingly.

Can't say I'm crazy about that mount by Novak. It seems to mimic the T18 factory adapter which is fine but the factory mount is wider and uses two bolts to the cross member.

 

Can you get pics of the driveshaft, trans output and pinion viewed from the side?

 

Yes, I can. I took the driveshaft out to get the angles. Easy to put back. The darn d20 has a high output point.

 

Here is a pic from the side and underneath.

This pic is as it sets now with no shims in the rear spring pads.

 

As was stated in a similar thread, with the cardan jointed shaft the pinion needs to be pointed directly at the transfer case output.

 

Will the d44 put up with that much angle and not complain with lack of oil to the pinion bearings?

 

Shouldn’t be an issue. There is a lot of oil slinging around to lube the bearings.

 

Well I double stacked the shims and no more vibes!! Driveline angle looks better now also. I was worried about the pinion angle.
Drove it up to 60 mph and seemed fine.
Thanks Guys
now i'll move on to other things
Tim

 

Good. That's slot of shimming I'd consider cutting the mounts and rewelding them.

 

You could move the fill hole up and put more oil in it. Add a little ATF to suppress foaming. I have a D44 cover that I just threw in the trash that you could weld a new bung in, if you want.

Or just force more oil in... the flow is slow enought that over-filling should be easy.

 

+1
Don't trust them. Stacked shims have a tendency to squirt out. At a bare minimum, get the proper 1 pc shims, or better yet, as Rich said, cut and turn the mounts.

Glad you got it figured out!

 

Here's what I learned about shims. I have 8° in mine. But the first shims I added were 5°. The locator hole on the spring pad became wobbled as the leaf spring center bolt wasn't fully engaged in the locator hole, because the shim caused it to be short... I found some shims online that had a flat machined into it so the nut sat flat. Added a longer bolt and life is good now. Someday I'll replace the pads. With all the shims you have in there I'd be a bit concerned..

 

The shims that I am using were made by a member here, and are machined the same way. New center bolt sets flat and proper in the shim, going through both.
I'm not worried much about it. I will revisit this and put in a single shim to take place of the stacked version.
Thanks All

 

You actually want about 1/2- 1 degree pinion down angle compared to the transfer case u-joint angle. That way under load they become pretty close to equal while driving. If you can find a Dana 44 high pinion cover from the front of a Ford or an aftermarket heavy duty cover they frequently have a higher fill plug to accommodate more fluid. The ARB heavy duty cover has both a drain plug and a dipstick built into the fill plug to check the fluid level.