Card in the spokes, but impending DOOM!

[78CityJeep]

Hey guys,
New to this forum and forums in general so please forgive me if I missed this in a previous thread. I did search but didn't find the prob.

Ok so I just purchased a 78 CJ7 .
360, currently T-150 , Dana 20 , AMC20 & Dana 30 . Pretty standard.

Test drove the vehicle and the Transmission pretty much sounds and feels worn out. Shifted smooth except into 3rd. Worn synchros.

My issue is this...
When driving in any gear as long as I'm loading the drivetrain it is quite (for a cj) but as soon as I coast/decal in any gear I get a loud card in the spokes gear noise. It's road speed dependent and very loud/solid sounding. I feel like it is the Transfer Case . Has one of those ridiculous U-shaped Transfer Case shifters and I haven't looked at the bushings but the shifter feels like I'm moving it through soft butter or pudding lol.
I have tried messing with the Transfer Case shifter and forcing it back into 2wd (not somewhere in the middle, which is what I ASSUME the issue is) but I was hoping someone had some firsthand experience with this.

Am I on the right track? Any advice would be appreciated.

 

[Lumpy Grits]

WELCOME!

Have you ck'd the oil levels?
LG

 

[cglax6]

What LG said...

Other things you may want to check if that doesn't help:

- u-joints on drive shaft

- driveline angles

When I purchased my 76, I had some similar symptoms. I'd get a little vibration when the engine and Transmission were under load, but the second I'd let of the throttle, it was the end of the world. Like that scene in Contact when Jodi Foster was shaking to all hell sitting in the seat. I digress...

Turns out the PO put in a Dana 44 in the rear to replace the Dana 20 and cut and rotated the spring perches to angle the pinion right at the output of the Transfer Case ...all while using a stock driveshaft. Turns out, if you use a driveshaft designed for a TC and pinion that are parallel in this kind of situation, it's bad news. I did some research, and asked a lot of questions here, and found my solution to be a double-cardan driveshaft. Basically a CV joint on one end of the driveshaft to make everyone in the driveline happy.

I narrowed down the issue to the driveshaft because I also thought the Transmission was toast because of all the vibration and scary noises. To do that, I removed the stock rear drive shaft and put the TC and 4HI and drove around in my new FWD CJ5 . No more vibration, and drove smooth as butter, thus eliminating the possibility of the Transmission or TC contributing to my issue.

When I installed the new CV drive shaft (that I got from Tom Woods), it drove smoothly again.

That being said, check your driveline angles. If they're off, that may be your problem.

Go to Tom Wood's website, they have a good explanation of what it all means.

Sent via Google translate using braille through Tapatalk

 

[78CityJeep]

Thanks for the reply.


I didn't check the fluid levels, but I assumed they were fine (I know...) because it didn't make the noise on the test drive. Literally only 12miles since picking it up and now it's doing it. I don't feel like it's a driveshaft vibe, it sounds more solid and it does it at any speed, even under 5mph or so. U-joints are brand new. Very solid.
When I had it inspected I could hear it in the parking lot about 100yrds or so away. It's def a solid gear noise.
I will look at angles in a couple days in case I've missed some detail while listening to it. I think this thing is stock height though. Only has 31s on it. Not positive though as it's my 1st CJ7 . The CJ8 I had came to me with 35s so that's no help lol.

I'll do some more digging and see what I find. That gives me a little idea of where to start though.

I actually have some of the stuff for an NP435 swap so maybe I'll just do that and rebuild the Transfer Case while I have it out. Was kinda hoping I could put all that off until I get married in Jan. Guess I'll tell the misses we won't be going on a Honeymoon because I'll be spending that money where it matters! Lol

Wish me luck

 

[JeeperChris]

"Happy Wife is a Happy Life".... Just say'in.

 

[78CityJeep]

That's totally true Jeeper Chris.
I may not be the smartest man alive but I would never tell her that in real life. It's fun to wish though.

 

[JeeperChris]

That's totally true Jeeper Chris.
I may not be the smartest man alive but I would never tell her that in real life. It's fun to wish though.

I know I'm not the smartest either cause I've had three of them ..hahaha.. Wish you all the best with your marriage!