TR Paul Posted August 6, 2017 Report Share Posted August 6, 2017 Evening chaps... I've recently noticed on TRoy (My 1970 TR6pi) an irritating 'clunk' from the vicinity of the rear axle (not unusual on a TR6, I hear you cry!). It happens when I take up the drive after gear changes, and can be remedied by being very gentle with the clutch. To my mind it feels like a U.J. This afternoon, as the sun was shining, I decided to investigate, but couldn't find any obvious problems: no noticeable play in any of the UJs, (which I greased whilst underneath;although I didn't remove the O/S driveshaft to check & grease the outer UJ), & all the diff mounting pins seem solid enough ( I replaced the front diff mounting bracket in 2014). The only issue I found was a an amount of play in the output shafts on the differential itself, but this has been like this in all the 10 years of owning the car.... Does this sound feasable, or am I missing something? Am I looking at a diff rebuild (hope not!!) As ever, your views & advice will be more than appreciated, Best wishes, Paul. Quote Link to post Share on other sites
RogerH Posted August 7, 2017 Report Share Posted August 7, 2017 Hi Paul, the drive shaft splines can also wear and give you that reassuring clonk. Roger Quote Link to post Share on other sites
harrytr5 Posted August 7, 2017 Report Share Posted August 7, 2017 If you are still on lever arm shocks check the securing bolts.I always fit longer bolts 2" and nyloc on the rears Regards Harry Quote Link to post Share on other sites
John390 Posted August 7, 2017 Report Share Posted August 7, 2017 What about the diff mounts themselves, they break away from the chassis! Cheers John Quote Link to post Share on other sites
Sapphire72 Posted August 7, 2017 Report Share Posted August 7, 2017 (edited) What about the diff mounts themselves, they break away from the chassis! Cheers John That's right. At the base of the right-front diff-mount pin, where it is fitted to the cross-member, a crack will develop from the torque twist of the diff in action. That area needs to be polished down to find the crack, then welded over and reinforcing plates welded on both sides of your recent mount. The exhaust system needs to be removed, as well as the diff, to do this repair. If you want to reinforce both front mounts, there is a brake line that should be removed. However, easy things first, remove the rear wheels, brake drums, and axles- then smear grease on the axle splines & grease those outer u-joints. See if that helps. Shift gears gently until then. Edited August 7, 2017 by Sapphire72 Quote Link to post Share on other sites
simonjrwinter Posted August 7, 2017 Report Share Posted August 7, 2017 If you need a diff rebuild, PM me and I'll tell you who NOT to go to! Simon Quote Link to post Share on other sites
harrytr5 Posted August 7, 2017 Report Share Posted August 7, 2017 Never had a problem with him Simon. Things can go wrong it is how it is dealt with. Regards Harry. Quote Link to post Share on other sites
Clarkey Posted August 7, 2017 Report Share Posted August 7, 2017 (edited) Hi Paul I had this It was indeed the diff mounting cracked around the pin, I have had this welded up and strengthened but I still have the clonk you describe new driveshafts and hubs fitted so the only thing that is left is the prop shaft and u j 's Edited August 7, 2017 by Clarkey Quote Link to post Share on other sites
simonjrwinter Posted August 7, 2017 Report Share Posted August 7, 2017 Never had a problem with him Simon. Things can go wrong it is how it is dealt with. Regards Harry. I don't think I mentioned who NOT to go to did I? Certainly it wasn't any of the well known Names mentioned on the forum. After an £800 bill and a 10 month wait, I think I'm probably qualified to advise who to avoid! Simon Quote Link to post Share on other sites
TR Paul Posted August 7, 2017 Author Report Share Posted August 7, 2017 Thanks for the advice. I will go down the easy (my favourite way!) route first - o/s drive shaft removal followed by greasing of splines & outer U.J. (I did the n/s one just before the IWE); I've also got a spare (good as new) drive shaft if needs be. My previous experience of diff mounting problems consisted of the front diff mounting bracket (the big one that is attached to the front of the diff and joins the diff to the chassis pins) breaking whilst pulling out of an Asda car park; This made an almighty 'bang', and made the car un-driveable over 20 mph; this is what I'd expect with diff mounting problems. However, it wouldn't be the first time I've been wrong about these kind of things (although I hope I am in this instance..!), & my experience is relatively limited. Again, many thanks for your help, Best wishes, Paul. Quote Link to post Share on other sites
harrytr5 Posted August 7, 2017 Report Share Posted August 7, 2017 Sorry Simon, I thought we had PM each other some time ago. Think the grey matter is going.... Regards Harry Quote Link to post Share on other sites
Sapphire72 Posted August 7, 2017 Report Share Posted August 7, 2017 Loose bolts attaching the lever-arm shocks have also been known to produce a clunk noise. It is rare, though, but easy to check with a spanner. Quote Link to post Share on other sites
TR Paul Posted August 8, 2017 Author Report Share Posted August 8, 2017 (edited) Thanks Sapphire, I'll have a look at that too; I've got Spax telescopics on TRoy, but their mounting brackets are fitted where the lever arms used to live. Best wishes, Paul. Edited August 8, 2017 by TR Paul Quote Link to post Share on other sites
peejay4A Posted August 8, 2017 Report Share Posted August 8, 2017 Your avatar shows steel wheels but if you're now running wires check that the mounting tapers on the hubs and wheels are dry, no grease. They can move around a little under braking and acceleration if there's grease present. Quote Link to post Share on other sites
stuart Posted August 8, 2017 Report Share Posted August 8, 2017 Your avatar shows steel wheels but if you're now running wires check that the mounting tapers on the hubs and wheels are dry, no grease. They can move around a little under braking and acceleration if there's grease present. They shouldnt move at all unless the splines are worn in which case they need replacing, I always grease all areas and then do them up tight, no noises. Stuart. Quote Link to post Share on other sites
peejay4A Posted August 8, 2017 Report Share Posted August 8, 2017 (edited) With new wheels and new hubs it happened to me Stuart. It doesn't take much movement for a detectable clonk. Perhaps I was unlucky but with dry tapers there's been no further problem. Edited August 8, 2017 by peejay4A Quote Link to post Share on other sites
TR Paul Posted August 8, 2017 Author Report Share Posted August 8, 2017 Thanks, Stuart/Pete, I am running standard bolt-on steel wheels. Cheers, Paul. Quote Link to post Share on other sites
pinky Posted August 8, 2017 Report Share Posted August 8, 2017 hi paul, after the international me and tors went to the lake district, the bracket supporting the kone shock absorber broke at the bottom, it started as a knock, then got worse I thought it was the exhaust, it was the bracket broken at the bottom, luckily a kind garage welded it up so I could continue, it now is in bits, being replaced, it's worth looking all over better on a car lift if you can , fingers crossed it isn't much of a problem pink Quote Link to post Share on other sites
TR Paul Posted August 13, 2017 Author Report Share Posted August 13, 2017 Hi fellow TR6ers, hope you're all well today. This morning, I removed Troys' n/s driveshaft, greased the outer u/j, cleaned, inspected & greased the splined section of the shaft. As I may have mentioned I've never had that one off the car (in 10 years).The splines were quite dry,& I could feel movement in the shaft as I twisted it in my hand. After replacing it all back on the car (and swearing a bit 'cause of the exhaust being in the way!), I went out for a test run in the glorious sunshine. Result: the 'clunk' would seem to have gone,for now; let's see how long that situation lasts for.... Many thanks for your help & advice, Best wishes, Paul. Quote Link to post Share on other sites
TR Paul Posted October 29, 2017 Author Report Share Posted October 29, 2017 Morning, fellow TR6ers. I believe that I have finally found the source of my infamous 'rear end clunks' & vibrations; After a couple of months of fannying about with drive-shafts, prop-shafts, UJs etc, I decided yesterday to bite the bullet, & drop the diff, so that I could inspect the mounting pins. To my (pleasant) surprise, the pins were in good condition, no splits or breakages etc, & as I suspected, a P.O. had reinforced & 'boxed in' the mounting with steel plating. What I did find was that the two rearmost mounting rubbers were shot, the steel tube had broken away from the rubber, giving the rear of the diff freedom of movement! On the one hand this was refreshing, in that it will be a (relatively) cheap & easy fix, but then on the other hand it is intensely irritating, as the rubber mounts are barely 3 years old! (I bought them from Moss in Oct 2014 when I had to replace the front mounting plate; wish I'd kept the old ones! ) A big thanks to all who gave advice on this issue , Cheers, Paul. Quote Link to post Share on other sites
ShaunC Posted October 29, 2017 Report Share Posted October 29, 2017 I've had the same issue recently and the vibration would show up on overrun at speed. One broken diff mount across the plate. Quote Link to post Share on other sites
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