Recon Diffs

[Dave M]

Just had some work done on my car and although the vibration is a lot less I still have a vibration and drone at around 50mph. The car has always had this vibration and despite fitting Datsun driveshafts and a cv jointed prop it's still there so I'm guessing diff issues. Can anyone recommend someone who can recon my spare diff?
I've also got non voided poly bushes on the diff carrier so I'm gonna change them when I swop the diff as I understand these can transmit noise and vibration into the car as they are too solid.

[GDPR]

Been very happy with the diffs I've fitted from Robsport - quiet and lash/vibration free....

No connection, just happy with the goods

[wilf]

Dave, are you absolutely sure it's not the exhaust where it runs through the rear subframes? I replaced the rubber mounts on mine ( the old ones were well perished) and very carefully centralised the pipes and it was a lot better.

[Dave M]

Dave, are you absolutely sure it's not the exhaust where it runs through the rear subframes? I replaced the rubber mounts on mine ( the old ones were well perished) and very carefully centralised the pipes and it was a lot better.

Don't think so Wilf as the exhaust doesn't touch the sub frame at all as I've checked that. Weird thing is when I had the work done on my car they found a lot of loose nuts on the drive shafts. I fitted nylock nuts when I did the shafts and if anything I over tighten stuff so I'm sure I never left them loose so what's caused them to loosen off, could it be the vibration from the diff?

[Dave M]

Been very happy with the diffs I've fitted from Robsport - quiet and lash/vibration free....

No connection, just happy with the goods

Thanks Russ, I know it's hard without seeing/driving the car but do you think I'm on the right track with the diff, everything else has been checked and tightened up this week and the car feels better but the drone/vibration still kicks in at around 50 and you can feel it if you drop down in speed through 50 mph.
Regards
Dave

[wilf]

Has your propshaft been balanced? Someone recently had a CV jointed one that was nbg from new. Tried giving the prop a good heave ho to see if there is any slack in the joints?

The nuts on my driveshafts were utter b's to loosen, someone had really done them up.

[Dave M]

Well I was a bit dubious re the prop as it has been sat in my garage for a year as a replacement for the previous cv prop that I found wasn't balanced and returned to RB :-( however my original prop had wear in the splines and the newly fitted prop if unbalanced is exactly the same as my standard prop because the vibration is identical to when the standard prop was fitted. Thing is the CV jointed end had to go at the diff as the holes wouldn't line up the other way around. Guys at YT think it may be the diff but without swopping parts it's hard to tell.

[Dave M]

Just been out in the Stag with the top up and to be honest it's crap at 50 mph severe vibration if held at 50, clears at about 65 not nice to drive with the hood up at all, really don't know where to go with it now, risk a diff? Gonna get the wheels balanced as there's a bit of judder on the steering at 30 but I don't think that will cure the vibration at 50 bloody car :-(

[PJM Stag]

Mike Papworth in Coventry did the diff in my TR6 and will get the work for my Stag later in the year. Nice guy, good work and recommended. No connection etc.

[jbuckl]

Rubber Diff bushes will help.

fwiw

Its quite easy to miss issues with the gearbox cross member & bushes when looking for vibrations.

Are the wheels concentric? (jack up and spin to check)

If all else fails, consider 'vibration free' to help your car.

Which reminds me, there are good vibrations and bad vibrations.....good vibrations were discovered in the 1960's

[Dave M]

Mike Papworth in Coventry did the diff in my TR6 and will get the work for my Stag later in the year. Nice guy, good work and recommended. No connection etc.

Ive e-mailed Mike as the guys at YT recommended him also, thanks.

[V Mad]

Weird thing is when I had the work done on my car they found a lot of loose nuts on the drive shafts. I fitted nylock nuts when I did the shafts and if anything I over tighten stuff so I'm sure I never left them loose so what's caused them to loosen off, could it be the vibration from the diff?

Long shot, but have you checked if the holes in and to the propshaft are worn? Any slight misalignment here will throw the whole lot out of balance even if the nuts are tight.

[Dave M]

Long shot, but have you checked if the holes in and to the propshaft are worn? Any slight misalignment here will throw the whole lot out of balance even if the nuts are tight.

The CV jointed prop was only fitted this week Chris and seems to have made no difference to the original one.

[KOY 23]

There was somone, can't remember who, who had a severe vibration from rear. I think they hadn't tightened the diff to body bolts, which fell out

Worth checking but I'm sure your car is maintained properly and the ginger nuts are tight.

[Dave M]

There was somone, can't remember who, who had a severe vibration from rear. I think they hadn't tightened the diff to body bolts, which fell out

Worth checking but I'm sure your car is maintained properly and the ginger nuts are tight.

All ginger nuts checked John and are tight, just paid to have the car given the once over as a I can't find the source of the vibration myself but the guys at YT can't find it either, next stage is to start swopping out parts. All UJs have been checked and are Ok so I'm thinking diff but really am frustrated with the damn car now as I just can't get it to drive as nice as it should. Guys at YT found some loose nuts on the drive shafts which surprised me but given the severity of the vibration at 50, maybe they have shaken loose but they were nylock so seems odd.