Shake and rattle???

Gobetjie · #1 (**permalink**) 03-05-2008, 08:01 PM

I am curious about this one. I have a 84 CJ7 that I bought in Nov. I have taken her out twice now not because of time but because I have to keep fixing things. I have Dana 44's taken out from a 69 International. When I bought the jeep the front yoke mounting bolts that holds the u joint in place had been sheared off of the rear axle . I replaced out the yoke. Now, this time I bent the bolts on the rear yoke and lost the u joint bearing caps in a Houston swamp. I am wondering if the rear axle is set at the correct angle? Another thing I wonder about that I think is related is when I am spinning the wheels everything rattles and shakes. The manual gear shifter and transfer case in particular go crazy, it doesnt pop out of gear. When driving normally it doesnt rattle. Another thing I noticed after driving back to the camp with only the front, if I took off the manual hub locks it would not move, is that normal or do I have a problem with the front axle? Let me know what you think.

Bounty__Hunter · #2 (**permalink**) 03-05-2008, 08:37 PM

Front axle hubs sound okay, sounds like you may have a problem with rear ujoint angles and maybe a bad tranny mount.

Can you take some pics of your rear driveshaft and ujoint angles?

Gobetjie · #3 (**permalink**) 03-05-2008, 09:40 PM

Here are some pics.

currupt4130 · #4 (**permalink**) 03-06-2008, 09:52 AM

If that's your rear axle the pinion should be parallel to the transfer case output (the same angle), not pointed at it. You don't have a CV shaft on it from the looks of things. That angle would be fine if you had a CV shaft, but with a single cardan shaft like that you need the pinion at the same angle as the transfer case output.

LBR · #5 (**permalink**) 03-06-2008, 10:30 AM

Agreed - when the yoke is pointed directly at the driveshaft it can't work as intended - the yoke and driveshaft have to be at interference angles or you get the shake, rattle and roll - if you shim the rearend downward several degrees you will notice it should be much better.........LBR

jfrabat · #6 (**permalink**) 03-06-2008, 11:07 AM

To me, it seems you are running SOA, so the angle may be too much for a single cardan srive shaft... You may still get vibrations even if you corect the rear angle. If I were you, I would get a CV shaft (then you dont have to touch the rear axle angle). That would reduce all your vibration issues.

Bounty__Hunter · #7 (**permalink**) 03-06-2008, 11:37 AM

I too would go with a CV rear driveshaft, which means a double-cardan joint at the transfer case end. It will likely require a new yoke on the transfer case.

Did you run in the mud/water with your brake lines FUBAR like they are in the pics? There is no axle vent tube to keep water out of the axle.

Bounty__Hunter · #8 (**permalink**) 03-06-2008, 11:39 AM

Tom Woods Custom Drive Shafts Custom Driveshafts Specialist

Gobetjie · #9 (**permalink**) 03-06-2008, 03:59 PM

Thanks for the advice. Will replace out drive shaft, There is a CV in the front. NO vent in the axle, how do I do that. As for the break lines should I tie strap them up or something. The emergency brake is not functioning.

Bounty__Hunter · #10 (**permalink**) 03-06-2008, 06:14 PM

I'm talking about the hard lines that are just hanging there, they should be fixed the axle. The rubber hose with the T on the end is usually attached to the axle breather, with a rubber vent tube going up high into the rear fender with a breather cap so it keeps moisture out. I'm sure your diff fluid is contaminated.

You may need a longer rubber brake line to go between the frame and the axle.