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Topic: Rear end thump, what to do. (Read 1540 times) previous topic - next topic

Re: Rear end thump, what to do.

Reply #20 –
I can maybe very very little move shaft slightly up and down. I just realized, I bought a pair of overalls for this occasion, now that I have my clothes all full of grease. Par for the course.

Re: Rear end thump, what to do.

Reply #21 –
Transmission Dampener
Barry seems to have a real good handle and understanding of this since he has been threw it. Would certainly think if it has been repaired or had the upgraded parts installed it should be with the prior records. Allison may even have history if they did the repair. I just reread the post and they go into good detail about it. You say that you think that there may be some play in it, I personally would want to get in front of it before it does any damage. Sounds like they changed the bolts and doubled the torque requirements on them to prevent. 4060 trans doesn't have these issues and was a contributing factor to wanting a 4060 rather than a early 3060 for me. Regardless if you don't know it's repair status it may be worth looking into farther. Please keep us updated.
Scott 🤞

Re: Rear end thump, what to do.

Reply #22 –
Ken, I would recommend buying a grease gun with a pistol grip pump--you can hold the hose on the grease fitting with one hand and pump with the other
Just my thought
Chris

Re: Rear end thump, what to do.

Reply #23 –

I can recommend the "Lock N Load" grease gun with an accessory easy lock coupler. Bought grease gun at Tractor Supply and it is designed to self bleed the air when changing over grease cartridges.

LockNLube Grease Gun Coupler locks onto Zerk fittings. Grease goes in, not on the machine. World's best-selling original locking grease coupler. Rated 10,000 PSI. Long-lasting rebuildable tool. Amazon.com: LockNLube Grease Gun Coupler locks onto Zerk fittings. Grease...

These two are worth the money in my experience.

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.

Re: Rear end thump, what to do.

Reply #24 –
Some other possibilities that can cause a thump to occur. 
Does this happen in third gear? with the 3060 it could be a shift solenoid.
Check your motor mounts, epically the rear.
Look at your trailing arms for a broken bolt.
Have you recently had the wheels off?  With your coach being a '97 you should have Budd wheels check torque on lug nuts. They changed to metric wheels on coaches between 5209 and 5212

Feeding the grease worms like have been touched on is a good start.

Mike

Re: Rear end thump, what to do.

Reply #25 –
Another diagnostic/repair option would be a visit to American Shifty co. in North Little Rock.  Others have had driveline issues addressed there, including the dampener and been pleased with the service. . Its kinda on your way home.

Re: Rear end thump, what to do.

Reply #26 –
I had a very heavy thumping noise on my 95 U320 when I would accelerate hard, then brake, then accelerate again.
I found it to be the rear bulkhead had enough play from the bolts rusting out that it was slapping and pounding the rear angle iron.

I cleaned it, cut away the fiberglass belly about a foot in front and cleaned out the rust, painted, and drilled through for new SS bolts . End of problem.

Check your FRONT and REAR bulkheads. If you see some cracking in the side wall of the coach down around where the bulkheads are, you might see the problem if that is YOUR problem.

Re: Rear end thump, what to do.

Reply #27 –
A bad or loose shock can make a crazy knocking sound too.

Re: Rear end thump, what to do.

Reply #28 –
Quote from: golfnut –
Hello forum members, I have been doing pretty good keeping Jor's old 34' going down the road. This is out of my knowledge though. I will post pics, I think I have that part figured out. We are at Enid Lake Mississippi. Very nice Corps. campground. Yesterday driving we started hearing some thunking, I just thought something was rolling around thumping in a cabinet. It got worse, wife says coming from underneath. It does seem to thump letting up, and then pressing down throttle pedal. Which I would imagine, could be what I am seeing in pics.
We were headed to Biloxi, but thinking at the every least we should head back towards home, which is about 600 miles to Missouri. Any knowledge and help would be much appreciated. Kim and Elana McCoy
Mine did that. Thought it was u joint. Sounded like running on rumble strip but not quite as loud. Turns out slide pin seized on passenger rear disc brake. Melted disc and rotor. Only noise when letting off and accelerating. No fun. Expensive lessons

Re: Rear end thump, what to do.

Reply #29 –
Kim,

Suspect you have concluded from the number of different things that can cause your noise that you HAVE TO determine the cause before driving very far.

Transmission and rear axle are the same (though in "backwards") as many trucks.  The air disk brakes are found on many fire trucks.  So, you should be able to find a HD truck mechanic to give it a quick look "under" to rule in/out the root cause.

Re: Rear end thump, what to do.

Reply #30 –
Good morning, we went to tractor supply in Batesville. Bought a lock n load grease gun, which is nice. Hit the drive shaft and u joints, no change in noise. Elana has termed it knocking, and says it sounds like it is coming from below floor in front of fridge. I have checked bulkheads everything looks good, has been repaired. Nothing that I can see with brakes. We are getting some oil around rear wheel outside dually (axle seal?) I have a shop near home, that I trust, would like to get there. Thanks

Re: Rear end thump, what to do.

Reply #31 –
Also checked shock bolts all good.

Re: Rear end thump, what to do.

Reply #32 –
Dose the knock increase with RPM and /or road speed,any chance of recording sound and sending it to one of our phones.

Re: Rear end thump, what to do.

Reply #33 –
It seems to be more of a suspension problem then driveline, but who knows. Kim

Re: Rear end thump, what to do.

Reply #34 –
That's funny, I was telling Elana around the campfire last night, that we should make a recording. Post it and call it Name the Thump.

Re: Rear end thump, what to do.

Reply #35 –
It doesn't do it shifting gears, or downshifting, or retarder use or braking. It will knock more like, in just the movement of slowing or increasing speed. Honestly, to me it sounds more like an old house settling on its foundation.

Re: Rear end thump, what to do.

Reply #36 –
Could be one of your torque rods bolt broke but unlikely,you can take a pry bar or big pipe wrench and wiggle/push to see if any play,you have 5 rods in back and 5 in front,rubber bushings could be shot,redid all mine years ago,it's a labor intensive job.

Re: Rear end thump, what to do.

Reply #37 –
"Elana has termed it knocking, and says it sounds like it is coming from below floor in front of fridge"

Are you sure your bowling ball didn't come out of its carry bag down in the basement?  😆🤣

But on a serious note, could it be something loose down in the basement?

Re: Rear end thump, what to do.

Reply #38 –
My vote goes to a shock bolt not tight enough and it is moving in the mounting brackets. We had that and one in rear just needed to be tighter.  Problem solved.
Johnh

Re: Rear end thump, what to do.

Reply #39 –
Looks like you still have the original Bilstien shocks,consider upgrading to Koni FSD,will be a world of ride improvement.