View Full Version : TR6 TR6! First Impressions and Rear End Noise!

04-06-2006, 07:44 PM
Well the neighbor I bought the TR from promised he'd wash it before I took it so he brought it by the house after and I got to take it for a spin....WOW ya gotta love that TR6 sound!..It runs like a dream and pulls strong, clutch is good and shifting is smooth, brakes are also great.

Now the bad part /ubbthreads/images/graemlins/nopity.gif
When I accelerate hard or let up on the clutch real fast I get the THUD from the left rear.....I know about the TR6 diffy mounts and the problems with them so it could be that....But I also thought this could be U-Joints? Any other ideas?
Either way not a big problem I feel real good about the car, I get ownership next weekend so I'll investigate further then....If it's U-Joints I'll replace them myself otherwise I'll bring it to the mechanic that did my MGB clutch.

R6MGS....+1 TR /ubbthreads/images/graemlins/driving.gif

04-06-2006, 08:24 PM
Sorry, but I've heard that noise before and I think your first guess is correct. A few years ago I bought one of those nightmare "all the parts are there, you just need to put it back together" projects. Didn't check the rear end then when I heard the clunking I found that the passenger front diff mount was completely gone and the PO had hacked in some cheap threaded rod to hold the diff in place. Very annoying but it was fixable once everything including gas tank was pulled and I got a welder to come over to fix things. So hopefully in your case it is just a u-joint, but don't despair even if you find it a little more involved - it can be fixed.
Good luck!

04-06-2006, 08:43 PM
well apparently the mounts have been welded already, that was one of the first things I asked him.....so I am hoping it's just the u-joints.....but even if it's a mount, I'll have it done in a shop, I don't have the time or facilities to play with that kinda stuff

04-06-2006, 09:26 PM
Best of luck with the new addition. U-joints usually will squeek on acceleration or grumble. It could be something simple like a broken exhaust hanger if your lucky. The drive train themselves are not the quietest & the axle splines , differential & u-joints all contribute to the knock.
It's best to get under the car & introduce yourself to your new friend. Shake hands with the U-joints & axle splines.

04-06-2006, 09:31 PM
I shook the exhast around and the hangar is somewhat lose but not enough the cause that.....I'll get under and take a good look when I get it next weekend.

04-06-2006, 11:12 PM
Another place you might want to take a look is at the yokes on the axle shaft. The PO of a 6 I used to own let a u-joint go for so long that the inner yoke busted two days after I bought it. Luckily I had a spare. Good luck, and congrats on the new addition. /ubbthreads/images/graemlins/thumbsup.gif

04-07-2006, 09:33 AM
Check the shocks mounting bolts and where the half-shafts bolt to the diff flanges. All of these bolts can loosen and cause clunking. They should be on a regular check list for tightening on all IRS TR's.

Good Luck.


04-07-2006, 11:22 AM
Thanks for all the great advice.....Here hoping that it's nothing too bad. /ubbthreads/images/graemlins/cheers.gif

04-07-2006, 01:45 PM
I vote U-joints. When my diff mounts let go, the metal-on-metal contact made a squeak. It sounded like a little bird chasing me where ever I went. It was much worse upon acceleration and deceleration.


04-07-2006, 02:49 PM
/ubbthreads/images/graemlins/lol.gif I am glad to hear that, lets hope your right /ubbthreads/images/graemlins/thumbsup.gif

04-09-2006, 12:22 AM
I too am investigating a rear end "clunk" when reversing in a newly obtained and slowly becoming roadworthy 73 TR6. I've been able to drive it just enough to get really excited about driving it more regularly.

Anyway, this evening I went through most of the rear end inspecting the u-joints, shock mounts, exhaust, etc and everything looks and feels solid (the "shaking hands" TRBoost referred to?). The only clue I got was if I rocked the raised wheel with the tranny in gear, the diff seems to move a bit more in the bushings than I would expect and emits a "squeak (it doesn't move THAT much, just a bit more than I expected under the load I was able to apply by turning the wheel) ". The notorious pax side fwd mount stud does not appear to move but is was difficult to tell. I'll take a closer look when I raise the right side tomorrow (I was working primarily on the left rear brake when I started poking around to look for the clunk).

My question is how much should the diff be able to move in the bushings? I'm planning to replace the bushings anyway and inspect the bracket, but if the opinion is almost certain that a mount is broken, I'll probably have someone do it for me because a welder I am not. Is it possible for the squeak/clunk to be caused by worn or old bushings without breaking the mount?


04-09-2006, 06:34 AM
For you new TR6 owners out there that have just acquired your treasures and plan on keeping them, a great weekend project (well, a long weekend perhaps) would be to take the rear suspension out completely and refresh all the things that might need refreshing. That is, unless you plan on doing a major restoration, where this would be part of the whole project. But I am talking about a car that is solid and you are happy with the mechanicals and might just need a new paint job. But areas on these cars (that often have had the odometer turn on them once) that just plain wear out are U-joints, shocks, mounts and other wear-and-tear factors. Even brakes. So, with that in mind and all your little replacement parts in hand, taking the whole rear suspension out is not that big a deal and you will get to inspect areas that probably will never be inspected again. Such as: are the splines on the drive shaft lubricated, are the 5 rear U-joints any good (probably not), is the infamous right-front diff mount intact (not necessarily in need of repair, tough to do with body on frame, can be done with experienced welder who likes to stand on his head and stack BB's) and an area that most everyone overlooks are the dreaded mounting bolts that hold the rear hubs into the aluminum swing arm. This area needs special attention in that Triumph used fine-thread steel bolts to screw into nice, soft aluminum. If these wallow out, you are in a heap of trouble. Mine had been repaired by the DPO with, of all things, JBWeld, g_d bless him. I HeliCoiled them all back and now are stronger than new. The only area most of you will need help in is lowering that diff by yourselves. A transmission jack would be handy or a strong late-teens son, the latter I used. Of course this is the time to change all your rubber bushings, including the ones on the swing arm. and send your shocks off to have them refreshed. (did I say weekend?) Or convert to tube shocks. And rebuild your rear brakes. And really clean the under-belly of your car, especially above the diff and in the folds of the rear wings. Oh, and you all realize that the exhaust has to come to do this, and taking an old exhaust system out often results in cutting it out.....

I am of the mind that if it has to come out, then do it all at once.


04-09-2006, 08:35 AM
/ubbthreads/images/graemlins/cryin.gif I wouldn't mind doing that, problem is I would never have the time to do that....or the room to have a car sit with the rearend out....This car probably won't get all that much use so I just want the clunk gone(that kinda stuff really irritates me). Unfortunatly I've got a list a mile long of stuff to do to the MG's so at this point I just want to get the TR noise gone and make the rest of it shiny again.

Countdown to TR6:
*6 Days* /ubbthreads/images/graemlins/driving.gif

04-09-2006, 09:51 AM
By the far the easiest way to start and the cheapest is to put that rear in the air, grab a few spanners and get to work. Check evey bolt you can find associated with the driveline. Do this even if your positive that a joint is your problem. You will most likely find at least a couple loose bolts. Don't be suprised if all eight bolts for the halfshafts to the diff are loose.


04-09-2006, 06:41 PM
I'll do that first, thanks

04-10-2006, 06:13 AM
One of the guys in the club had that same kind of clunk in the rear of his TR6. It turned out to be the diff mounts. NOT where the brackets attach to the frame, but the actual rubber mounts. We changed them out, and everything was fine again. If you jack the rear up and work the wheels back and forth, if the rubber mounts are bad, you will see and hear the diff flopping around.

FA Gordon
04-10-2006, 07:54 AM
Swift6 mentioned shock mounting bolts. My rear end clunk was from the tube shock mounting brackets the po had installed when he swapped out the old shocks. The bracket bolts had loosened and it made a nasty clunk.