The Tail Of 2 Transmissions

So boys and girls today's story is about 2 Jeep T18's and a 73 CJ5 built out of 3 piles of parts. The jeep in question has a 4.3L, TBI gm V6, NOVAK adapter GM engine to a Jeep T18. I had 2 T18's, I picked the one I knew was ran in another CJ5, bad choice. The 2nd gear synchro was non-existent and popped out of third gear on decell.

I pulled out the spare, rebuilt the transmission with a NOVAK kit, No major issues noted during dis-assembly. The trans was reassembled, shifted smooth on the bench. I inspected the transfer case, no trash in the pan, all looked good, new seals and installed on the trans.

I swapped out the trans/case with little issues. So, now starts the fun, I have a heavy growling noise during coasting. There is no noise under load/accelerating or decell(clutch out, in gear). The noise is present above 30 mph, clutch in(on the floor), trans in gear or neutral.

Any ideas are greatly appreciated, I'm not in a hurry to pull it out, but I know I will.

Is there any thing in the transfer case that could cause this type of noise?

This isn't the first trans I've rebuilt.

Thanks for your time. Ron

 

Classic u-joint noise.

 

Yeah, check the phasing of the rear driveshaft, and make sure the u-joint angles match.

 

Thanks, I'll double check. I didn't have the noise before the trans swap.

Also, with the transfer case in neutral, trans in 4th gear, running the engine at highway speed, no noise.

Thanks again, Ron

 

Yes, but you had the driveshafts out, might have reassembled them in a different orientation.

 

very possible, Ron

 

measured phase angle of rear drive shaft(adams), <1*.

thanks yall, Ron

 

Just a thought, might try just removing the rear drive shaft and drive around some with just front wheel drive and see if the problem persist or goes away..

 

I'll try that tomorrow nite, Thanx, Ron

 

I'd like to thank all the reply's. I checked/performed as recommended, no problems found. Thanks again.

So, I took it on a 40 mile ish drive on the free way. No noise under load or coast clutch out.

So, on Thursday I formulated a plan and wrote it on toilet paper(so it had a purpose after execution). I was off work early on Friday, so I prepped a spare dana 20 transfer case.

Saturday I rolled the jeep into the garage, pulled the transfer case. I disassembled the transfer case, NO problems found. Small amounts of glitter, but not enough to worry about. Looking at the end of the transmission I decided I'd pull the transmission.

I disassembled the transmission, NO problems found.

I was on the FAR SIDE of disgusted.

I decided to pull the cover on the rear end(also rebuilt), nothing wrong.

Sunday I reassembled the transmission, now waiting on gaskets.

This weekend I'm putting it back together, with plans on driving it till it gets worse or it explodes.

Thanks again all. Ron

 

How's the stay cable

 

A 73, it will have a D20. These are VERY particular to driveshaft angles being correct. Nothing was mentioned in your follow-up about the rear driveshaft, u-joints, phasing, etc… except for:

…which I’m unclear about. Is the rotational input/output <1° out? As in, if you rest the shaft on a flat surface, do the (matching, not opposing) u-joint caps sit flat?

Or are the angles <1° different?
So, for example, if the angular difference between your shaft and t-case is 5°, then the angular difference between the pinion and the shaft is around 4° or 6°?

A pic of your rear shaft in place would help put this part of it to rest.

 

Sorry, the drive shaft is in phase. I'll have to remeasure the angles once it's back on the ground. Thanks, Ron