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Recently in my '99 C2 Tip, when in 5th at about 35 - 45 mph (low rpm) and coasting with no throttle, I noticed the slightest of a whine from the rear. Its like a soft woo sound. I don't think its transmission noise as I manually shift down to 4th and 3rd and there is no change in the pitch. I don't hear it any other time. Its no worse cornering. I jacked the car up and there is no rumble from any wheel when I spin them. Maybe its my imagination but could it be the start of my wheel bearings?

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Recently in my '99 C2 Tip, when in 5th at about 35 - 45 mph (low rpm) and coasting with no throttle, I noticed the slightest of a whine from the rear. Its like a soft woo sound. I don't think its transmission noise as I manually shift down to 4th and 3rd and there is no change in the pitch. I don't hear it any other time. Its no worse cornering. I jacked the car up and there is no rumble from any wheel when I spin them. Maybe its my imagination but could it be the start of my wheel bearings?

i would jack it up, remove the wheel, and for convenience the brake caliper, then grab the rotor at the 3 and 9 o'clock positions and rock it and try to wiggle it. Do the same for the 12 and 6 o'clock positions. Movement, assuming the axle nut is tight, usually means wheel bearing. But also spin the axle and listen to the inner CV joint.

any recent brake work in the rear? new pads or rotors?

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Recently in my '99 C2 Tip, when in 5th at about 35 - 45 mph (low rpm) and coasting with no throttle, I noticed the slightest of a whine from the rear. Its like a soft woo sound. I don't think its transmission noise as I manually shift down to 4th and 3rd and there is no change in the pitch. I don't hear it any other time. Its no worse cornering. I jacked the car up and there is no rumble from any wheel when I spin them. Maybe its my imagination but could it be the start of my wheel bearings?

How many miles on your rear tires?? If it isn't the bearing, I would bet it's the tires if they are beyond 50% worn. Many other incidences of this "noise issue" when you have wide rear tires at 40psi or more.

My $.02 Demosan

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Thanks guys, there's definetely no movement trying to rock the wheel and there is no rumbling when spinning the wheel. Will listen out for the inner cv joint. Funny I did think it was the tyres (3mm left) so I changed them, actually got new tyres and new 18 inch Sport Design wheels to replace original 17s but it made no difference. Will try the lug nut temp test later. I do think its early days of worn wheel bearings.

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It could be a resonance noise coming from the differential part of the Tip. if the noise is only speed related, 35/45 mph. independent of the selected gear. You have to diagnose this issue more precisely, it could be a lot more.

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  • 2 months later...
Did you find a solution to your problem? i have the same problem and i am interested to know how you sorted it out???

thanks

Rear wheel bearings both replaced which helped the noise. There is still a faint whine off throttle about 40-45mph and it could be tyres or early worn diff although you would expect to hear more with a worn diff. Happy with car at present.

Edited by minny
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Did you find a solution to your problem? i have the same problem and i am interested to know how you sorted it out???

thanks

Loren mentions tyres as a posiible source of the noise, my 99C2 had this problem, sounded like very worn wheel bearings and was most noticable around 30mph, a new set of rear tyres fixed it completely

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  • 1 year later...

It could be a resonance noise coming from the differential part of the Tip. if the noise is only speed related, 35/45 mph. independent of the selected gear. You have to diagnose this issue more precisely, it could be a lot more.

Resurrecting an old thread here... I have a noise that sounds as if it is similar to what you describe. It occurs between 25-35 mph... on my 2000 Tip C4. It really sounds as though it is coming from the right front, however. It doesn't sound like bearings, but it could be the CVs need to be serviced. How much lock up is there at the front wheels at this speed? I am suspecting that it may be that as the viscous dif powers up the front wheels a bit, it is causing the CV to "groan" a bit. There is no clicking noise and it does not change with RPM or gear selection. I am going to service and replace the boots on all the CVs as soon as my parts arrive...

What does a CV joint that is going sound like on a C4- the same as any other vehicle? Any thoughts? Thanks!

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