so
#1
04-20-2017 | 09:42 AM
so
A while ago I had a post regarding my car 'rumbling' after 50 mph, perfectly quiet and smooth before that speed. It never changes due to the UK climate, hot or cold, dry or wet, driven carefully or hard. From day 1 the car has done this, and after replacing every bush, joint, and bearing under the car - front & back I still have this rumbling at the same speed, gradually getting less up to 70 mph but, still there. I read other posts re changing out the diff bearings but, I'm not sure the right way to go. Are the diffs (and/or its bearings) known to be a problem, or the prop-shaft an issue, maybe the jurid couplings? I'm sure people will have different stories about their own experiences, but what I'm hoping to find is someone who has had a very similar issue with their car and how they cured it.
Having changed everything else under the car, and using the sometimes unreliable theory of elimination, I guess the only area(s) to look at must be from gearbox to rear drive axles (the output axles' U/J's have been renewed there too). Nothing, from the gearbox end jurid coupling towards (and including) the diff have been touched except the diff carrier has renewed bushes. So anyone experiencing similar problems please let me know if you cured the problem, and how?
Only other thing to mention, that may be totally unrelated, is braking hard at a decent speed... the car shudders, as if I had a warped disc, though they were renewed less than 3k miles ago. I'm just wondering if the hard braking is highlighting whatever it is causing the rumble, though it may be a totally different issue as said.
I did also mention in the previous post that it feels like a bad prop-shaft U/J problem I had years ago on an old Mk3 Ford Cortina (there's a blast from the past) which caused that car to rumble, but that 'eased off' when feathering the accelerator, on the Jag it's still there even if I knock it into Neutral? BTW, it stops immediately I drop below 50 mph and comes back if I accelerate again.
Whilst I accept it would be a rare sight to see one of these cars running completely problem free, this issue really is letting the car down after having so much done to it to keep it running as best as it can. Any help and advice is greatly appreciated as always.
P.
Having changed everything else under the car, and using the sometimes unreliable theory of elimination, I guess the only area(s) to look at must be from gearbox to rear drive axles (the output axles' U/J's have been renewed there too). Nothing, from the gearbox end jurid coupling towards (and including) the diff have been touched except the diff carrier has renewed bushes. So anyone experiencing similar problems please let me know if you cured the problem, and how?
Only other thing to mention, that may be totally unrelated, is braking hard at a decent speed... the car shudders, as if I had a warped disc, though they were renewed less than 3k miles ago. I'm just wondering if the hard braking is highlighting whatever it is causing the rumble, though it may be a totally different issue as said.
I did also mention in the previous post that it feels like a bad prop-shaft U/J problem I had years ago on an old Mk3 Ford Cortina (there's a blast from the past) which caused that car to rumble, but that 'eased off' when feathering the accelerator, on the Jag it's still there even if I knock it into Neutral? BTW, it stops immediately I drop below 50 mph and comes back if I accelerate again.
Whilst I accept it would be a rare sight to see one of these cars running completely problem free, this issue really is letting the car down after having so much done to it to keep it running as best as it can. Any help and advice is greatly appreciated as always.
P.