High pitch noise 65-80 mph
 

New to forum and looking forward to the LR conection.
Just purchase a pre-owned 2000 Discovery w/ 74k miles. We really like the vehicle but it has a couple of issues and wondering if it is normal or if we need to seek attention.
1) It has a high pitch noise when accelerating at speeds from 65 to 80 mph on the highway. It will drive you crazy unless the tunes are cranked.
2) I may need to post this separately but it also has a vibration at the same speed.

Thanks!

I'm experiencing the same "high pitch noise" when accelerating, any clues? ...although this guy last posted in 2005! PLOP

Remove the 2 driveshaft, starting with your front 1 first. Check range of motion on Ujoints especially at the double-cardan. There is also a centering type bearing in there. You have to rebuild it with greasable Zerk Ujoints or purchase an aftermarket unit. The rear can be rebuilt fairly easily and on the cheap. Mark with a punch how the DS is oriented on the truck before it is removed as it must go back exactly the same way. If the wine comes with any vibration that is a sure sign or driveshaft failure.

Do a search on driveshaft failure. There are some new, ongoing threads also discussing the subject

...thanks CHUBBS878, I'll search around, but would you happen to know why does it make that sound, does it mean is on its way to break? ...the front driveshaft (DS) already broke off once, from the transfer case (TC) side... left some battle scars here and there, and replaced it with a used one; it has been holding pretty well, so I thought; I already replaced the U-Joint some time ago on the same old DS, on the TC... I guess this sound is just another way to tell you it's gonna fail, besides the known shaking while accelerating from low speeds to higher.

It broke once and the only damage was dents and dings, you got lucky; usually the result is a hole busted in the transmission so you end up having to replace that, as well as the driveshaft. (that's expensive) If you replaced the DS with a used piece that is OEM with greasing zerks deleted, you will have the same problem as the last time. The upgraded DS allows for greasing at each & every Ujoint to prevent premature failure. So, you can either rebuild the current DS with all greasable Ujoints or just buy another upgraded unit for $200 as it costs about $100 and usually the whole weekend for a DIY rebuild. You have to replace the little hidden centering-bearing which runs $40-$50 alone.


But yeah, squeaking/whining noises with vibration at speed is usually result of a failing Ujoint. The unit/units are no longer able to properly distribute the internal grease to each end cup where the needle bearings lie, would be my guess. There are 100 threads about front DS failures, sign/symproms, replacing and so on.


The sounds and vibrations could possibly be from something else, I just suggest that you start with inspecting your DS. Don't completely neglect the rear as it also needs R&R; it doesn't get addressed as often because a failure doesn't necessarily destroy part of the drivetrain as with the front 1.

Don't screw with that noise.

Lube the drive shafts - ASAP.
At least do that.
And then drive it and let the lube work in.

Put the grease gun on the Zerk fittings and pump some good grease into the driveshafts .
I had this same problem.
I was going across country from Colorado to Seattle.
I put lube in to the drive shafts in Ogden Utah.
Drove back to Seattle.

And never a problem after that!

...thank you CHUBBS878 & JFALL for your feedback!

Does the DS need to be removed in order to re-grease the U-Joints, or is it something that can be done in place?

If removal of DS needs to be done, how hard can it be to do so, or what to expect?

From what I remember, the U-Joint I bought at Advanced could be re-greased if needed, the front U-Joint I don't know, 'cause that one didn't need replacement.

Thanks again!

There is no need to remove the DS but need to raise the truck incase the nipple is on top and cant be reached. If your truck is lifted, and you can slide under then it will be easier. Just move car forward and back to reach the grease points. Removal need 9/16 open wrench and 2 of them.

There are dozens of threads on this so I suggest doing a couple hours search because there's more to it than "lube the DS and rock on."