rummbling when at 50 mph

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Budgie
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rummbling when at 50 mph

Post by Budgie »

Well I have taken my tourer on another run , the second since having the gearbox rebuilt and changing the front universal joint on the prop. But when I reach around 50 mph there is a distinct but light rumbling noise with a slight rapid shake from the steering wheel. Any thoughts folks, new universal joint possibly ? By the way all grease nipples were re greased, not that they needed it, and I had new king pins and trunnions two years ago and new front wheel bearings.
greendefender123
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Re: rummbling when at 50 mph

Post by greendefender123 »

Does it only do it in gear? Does the sound change on over run and under load. If your feeling it alot through the steering id be checking the front wheel bearings, even tho you've changed them. Iv had loads ujs go on different cars and land rovers. I do alot of car trialing. Just double check the circlips are still in place and that the cups are fully seated. Iv had it before/not fitted them properly due to being in a rush and not double checking. you can normally feel slight movement in the propshaft.
robandsophie
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Re: rummbling when at 50 mph

Post by robandsophie »

Could be wheels; often can loose a weight from rim when removed. Also tyres can start to deform (depending on make). Easiest thing take it to a tyre fitter get them to have a look (re-balance) could be nice and cheap job! :)
beero
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Re: rummbling when at 50 mph

Post by beero »

Put the rear axle on 2 axle stands and run it up to 50. If there is no rumble you then know it is from the front end. You could then swap wheels from front to back and do it again, that would check for wheel balance.

MarkyB
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Re: rummbling when at 50 mph

Post by MarkyB »

Another vote for out of balance wheels, 50 mph is the speed that it really shows up.

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Nickol
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Re: rummbling when at 50 mph

Post by Nickol »

What about getting it up to Speed and then taking it out of gear. Do the vibes then stop? If not, it would rule out gearbox/ engine induced harmonics.
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Budgie
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Re: rummbling when at 50 mph

Post by Budgie »

Well I have replaced the rear uv joint and it did have a slight bit of play but not as much as the front joint and even that wasn't a great deal. I just need to take her out on a test run when it's dry and I'll also do the tests as suggested .
greendefender123
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Re: rummbling when at 50 mph

Post by greendefender123 »

Fingers crossed.
Budgie
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Re: rummbling when at 50 mph

Post by Budgie »

Well as I at first suspected [and hoped] , it was the rear universal joint on the prop shaft. I took the car for a good run today touching speeds of almost but not quite 60 mph,[and on numerous occasions too, I know staggering innit ] and not a rumble or judder to speak of ...well chuffed . :D But what puzzles me is why no such issues before I decided to change the front uv joint which had hardly any play and only on one bearing ? And when I checked the rear one at the time of checking / changing the front there seemed no play at all .Ah well at least all's well that ends well . :D
Trickydicky
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Re: rummbling when at 50 mph

Post by Trickydicky »

The most probable reason is that the propshaft was not refitted in the same position as it was taken off. When removing a propshaft, marking the flanges with a centre punch mark ensures it goes back in the same position.
Richard

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Budgie
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Re: rummbling when at 50 mph

Post by Budgie »

Yeh I did the centre punch thing but can only assume that it had "bedded in" during wear and compensated it's self whereas when I changed the front it "threw" the balance out by one good tight fitting uv against the other....at least that's all I can conclude. :-?
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