simonjrwinter Posted November 25, 2015 Report Share Posted November 25, 2015 OK, not a happy bunny at this point in time..... Just drove my car for the first time since the diff was rebuilt. On acceleration and deceleration, no noise at all....however.... at a constant speed it's like a 1940's lorry gearbox, the whining noise is horrendous almost deafening! Yes, it does have oil in. I replaced the bushes with poly ones but I'm sure it's nothing to do with that, is it likely to just be badly adjusted? Simon Quote Link to post Share on other sites
Guest ntc Posted November 25, 2015 Report Share Posted November 25, 2015 OK, not a happy bunny at this point in time..... Just drove my car for the first time since the diff was rebuilt. On acceleration and deceleration, no noise at all....however.... at a constant speed it's like a 1940's lorry gearbox, the whining noise is horrendous almost deafening! Yes, it does have oil in. I replaced the bushes with poly ones but I'm sure it's nothing to do with that, is it likely to just be badly adjusted? Simon Yep Or repro CWP Quote Link to post Share on other sites
Bill Bourne Posted November 25, 2015 Report Share Posted November 25, 2015 Hi Simon Ditto... mines just been re-built and I've only done about 1,000 miles. So I'm taking mine out again this weekend and then back to the re-builder next Friday 4th. I'm told that it could possibly just need re-shimming and after a re-build, that is a strong possibility. I hope so. If not I'm not sure, I guess crown wheel and pinion is at fault. Like you. mine only whines (not too loudly though) when travelling at a medium/constant speed. Best Bill Quote Link to post Share on other sites
Guest ntc Posted November 25, 2015 Report Share Posted November 25, 2015 Food for thought , the diff should be driven gently for the first 50 miles,and that is from somebody that does know his eggs. Quote Link to post Share on other sites
elclem1 Posted November 25, 2015 Report Share Posted November 25, 2015 Were they refurbed at the same place? Quote Link to post Share on other sites
marko Posted November 25, 2015 Report Share Posted November 25, 2015 There is a difference between gear noise (CW & P) and bearing noise.....Gear noise is more of a "whining" noise at constant speed and bearing noise more of a "drumming" you need a good ear to hear the difference If it's gear noise (sounds like a 1940's lorry) then it doesn't matter how long you drive it, it won't get any better - New Crown Wheel and Pinion required..... If the diff has been rebuilt then I suspect you should have new bearings..... My money is on you need a new Crown Wheel and Pinion... Quote Link to post Share on other sites
elclem1 Posted November 25, 2015 Report Share Posted November 25, 2015 But if the the diff was rebuilt wouldn't the cwp been checked at the same time? Quote Link to post Share on other sites
barkerwilliams Posted November 25, 2015 Report Share Posted November 25, 2015 How do you know the noise is coming from the diff? Have you been able to confirm it is the diff or are you just assuming it is because it has just been rebuilt? Alan Quote Link to post Share on other sites
simonjrwinter Posted November 25, 2015 Author Report Share Posted November 25, 2015 The diff is the only thing that's been changed. A missing tooth in the cw means the cw&p was replaced with a good matched pair. No accusations made here about the rebuilder, it's entirely possible it's been installed incorrectly (by me) in the car. I'll investigate further and report back. Quote Link to post Share on other sites
stephen cooper Posted November 25, 2015 Report Share Posted November 25, 2015 I have had two noisy (whine) diffs over summer. One reputedly had a new CW&P. Got a quiet one now thankfully. Now polybushed which seems to have created more noise at motorway speeds though so think I'll hunt out some OE mounts if possible. Anyone know a good source mindful of modern rubber... Cheers Quote Link to post Share on other sites
Steves_TR6 Posted November 25, 2015 Report Share Posted November 25, 2015 (edited) I have had two noisy (whine) diffs over summer. One reputedly had a new CW&P. Got a quiet one now thankfully. Now polybushed which seems to have created more noise at motorway speeds though so think I'll hunt out some OE mounts if possible. Anyone know a good source mindful of modern rubber... Cheers On my last car the fitment of polybushes made the diff considerably more whiney. It may have whined before but was a real pain at motorway speeds after the blue polybushes were fitted. Steve Edited November 25, 2015 by SDerbyshire Quote Link to post Share on other sites
Guest ntc Posted November 25, 2015 Report Share Posted November 25, 2015 The poly mounts should make no difference . Quote Link to post Share on other sites
GT6M Posted November 25, 2015 Report Share Posted November 25, 2015 If itsa new CW.P, {german origin }, then the ones ive re done are a pig to get a pattern on drive side, And also not round,!!! best to go by pattern on coast side Also, has the contact patch been done with alott of load onit as the pattern changes alott wid load. if set with oot, then when under load, contact pattern can be 3/4 way up, and off the tooth Also, gotta check the pin pattern too, see where its running Also, the v hard mounts will send a drumming noise thru at certain speeds, mainly high speeds, I took mine oot, as owa 4.5 in OD top, it was really bad. If its a used one, then some are near on impossible to get a contact pattern on drive, gotta go by pinn and coast markings On a used set, changing contact patch alot in /oot mesh, can have funny results, as diff gears are then running on unworn bits, which can lead to noise. an localised heat on gears Some one said this Food for thought , the diff should be driven gently for the first 50 miles,and that is from somebody that does know his eggs., strange comments, as not long ago , some one was advocating driving it as hard as poss, when some one was asking about a diff break in, most odd , maybe found some thing out since then. care to share.!! M Quote Link to post Share on other sites
GT6M Posted November 25, 2015 Report Share Posted November 25, 2015 The poly mounts should make no difference . Ohhh yes they doo. and Im not alone in thee,s findings OK if pottering aboot, but not at speed prob nowt to worry about on a track car only, but for a road car, forget em M Quote Link to post Share on other sites
Guest ntc Posted November 25, 2015 Report Share Posted November 25, 2015 (edited) M I have no idea who you are but you are incorrect,yes I made the first comment .Roy Talbolt has built all my diffs and not one both road and track use has failed or made noises poly mounted or not,if you know better than him I don my hat to you. Edited November 25, 2015 by ntc Quote Link to post Share on other sites
GT6M Posted November 25, 2015 Report Share Posted November 25, 2015 No im not incorrect on hard bushes, Yes.. maybe your hearing no so good though, and also yer arshe end aint as good as picking up what the cars saying to ye as mine is. But hard poly bushes doo make a noise, esp on smaller chassis cars, as can be verified by lots of others, care to go ask on Spitty /herald forum then see / read all the evidence. as for driving it hard, this was on a post ages ago, go find it and bung it up. again, correct, yes And yes, i prob doo no as much or equal to him, been at it lang enough just cos I aint got ..specialist, infront or after me name, or is it that just so called specialists can doo TR work,!!! why not build yer own diffs, there nowt hard aboot em, just basic common engineering practice So thanks for donning yer hat to me, M Quote Link to post Share on other sites
Guest ntc Posted November 25, 2015 Report Share Posted November 25, 2015 Then tell me his and your history . Quote Link to post Share on other sites
Marc R Posted November 25, 2015 Report Share Posted November 25, 2015 Hi M. I am not English native and it is difficult for me to understand your way to write (like if you speak) in English. May I ask you to make an effort Thanks' and regards Quote Link to post Share on other sites
Tom Boyd Posted November 25, 2015 Report Share Posted November 25, 2015 Sounds like the cwp is incorrectly set. Yes poly bushes can transmit noise into the cabin. Quote Link to post Share on other sites
simonjrwinter Posted November 25, 2015 Author Report Share Posted November 25, 2015 HOLD EVERYTHING!.... Just been back to look at the diff and it seems the rear bushes may have been fitted upside down.... I fitted the new (poly) mounts in exactly the same way the old ones came off.......it looks like they have been fitted wrongly by the previous owner 20 years ago. When removing the diff, I noticed witness marks on the top of it. It's obviously rubbed over the years but maybe only occasionally, not enough to cause a huge issue. Replacing the bushes with new poly bushes has obviously brought the diff into harder contact with the chassis and the sound is being transferred directly to it. I was very careful to replace the bushes in EXACTLY The same orientation as they came off, but looking back over previous posts, it seems they were wrong all along! The diff rebuilders reputation is unblemished! Phew! Simon Quote Link to post Share on other sites
Guest ntc Posted November 25, 2015 Report Share Posted November 25, 2015 Yes poly bushes can transmit noise into the cabin. On this I still disagree even with alloy cups. Quote Link to post Share on other sites
Guest ntc Posted November 25, 2015 Report Share Posted November 25, 2015 HOLD EVERYTHING!.... Just been back to look at the diff and it seems the rear bushes may have been fitted upside down.... I fitted the new (poly) mounts in exactly the same way the old ones came off.......it looks like they have been fitted wrongly by the previous owner 20 years ago. When removing the diff, I noticed witness marks on the top of it. It's obviously rubbed over the years but maybe only occasionally, not enough to cause a huge issue. Replacing the bushes with new poly bushes has obviously brought the diff into harder contact with the chassis and the sound is being transferred directly to it. I was very careful to replace the bushes in EXACTLY The same orientation as they came off, but looking back over previous posts, it seems they were wrong all along! The diff rebuilders reputation is unblemished! Phew! Simon Good news Quote Link to post Share on other sites
SeanF Posted November 25, 2015 Report Share Posted November 25, 2015 Good news Simon. Let's hope that solves the problem Sean Quote Link to post Share on other sites
Nigel Triumph Posted November 25, 2015 Report Share Posted November 25, 2015 Glad you've got to the root of the problem. As for Polybushes increasing diff noise, from my experience on a GT6, the blue bushes made no difference. I recently replaced old rubber with new blue poly. The new bushes seemed softer or more compliant than the old when fitting them. There's no discernible difference in noise from the diff, and that includes some hard driving. Perhaps the red competition bushes would transmit more noise, as they are much harder. Nigelk Quote Link to post Share on other sites
elclem1 Posted November 25, 2015 Report Share Posted November 25, 2015 Marc r. The above is just genial banter Between enthusiasts I am sure. Ntc is doing the Yorkshire thing by getting his point across in as few words as possible, M comes from Glasgow I think. I can equate to the conversation having lived in SW France for 7 years and trying to understand the accent here you have to be tuned in to it it isn't Parisienne French!!! It's made my day! Quote Link to post Share on other sites
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