Hi There , Not really New to Forum. Whats Going on with all The changes why fix something if itīs not Broken ????????? Had to register again. because I couldīnt get my Pasw.

Well I still Have a Virbatión at arround 80 MPH when decelerating or letting go of Accel. ( 2003 ) disco 90 K. It feels like in the rear of Truck , Not on Weel and itīs a deep Humming Vibration that goes away inmediately after accelerating again.

So Far I,ve Changed.

U Joints. All 4
Center Ball. Kit or precision 617 Kit.
Roto Flex.
Front Drive Shaft. ( New)
Hubs.

Serviced Tranny, Disco Mikes way.
Repaired T Case for a small Leak.
Balanced Tires ( Twice )
Breake Pads ( also Twice )
Balanced Rear D Shaft ( Just in case )

Tranny and Engine Mounts. Seem OK ( No cracks )
Oil in Differentials seem Fine but a Little dark.
Parking Breake is also OK.

Ive been spending Money and looking for the source of vibration for over a Year and cant seem to Find what ever itīs causing it. Im also looking at the rear diferential with suspicion as well as the rear drive shaft.

Does any body Out there Know what can cause these vibration other than the things Ive Replaced or fixed?

Soundīs Like a real Puzzle Right?

 

Yea...this is a tough one and beyond my expertise...I would suggest quit going 80 MPH!!!!!

 

Ok since it appears you are in the process of doing a complete rebuild of your vehicle heres my 2.7 cents (along with stop speeding).

A. Are your tires rated for high speed?

B. How worn are your tires (rotating and balancing will not correct major cupping)?

C. How big are the lugs on your tires (if you are always doing 80 you need some panzy street tire not super swampers)?

D. Do you have a broken belt in one of your tires (balance and rotate changes vibration from front to back - vis-versa)

E. When was the last time you repacked/replaced your wheel bearings?

F. When was the last time you repacked/replaced/retorqued your pinion bearings?

G. Have you ever had the "mesh" of your ring and pinion inspected/verified (you may need a new set)?

This list is in order of cheapest to expensive, you do knot have to respond (kan if you want) but these are questions I would ask not knowing or seeing the vehicle.

PS

As a last resort throw the keys to someone you REALLY trust and give them a range of speeds (none of which I'm giving permission for) and ask them to take it out to see if they feel anything. Dont try to compare the ride of a tank to your moms Lexus.

Enjoy

Robert

 

Thanks Night Train.

A.- Tires are Rated H witch is for 130 MPH
B.- Tires have about 40% Life Left. and seem evenly worn
C- Lugs ?? Tyres are 255 55 r 18 Toyo ( Japaneese I guess )
D.-No Belts or apparent damage to Tyres.
E.- weel bearings , Never changed.
F.- Pinion Bearings , Never changed.

Iīm on the phone with work shop as we speak and told them about all your questions.. He said that Vibration is not constant or goes away inmidiately after resuming acceleration. and all of your questions would suggest a constant Vibratión. Right?

I Love my Tank but Iīm really getting tired of not being able to Use it and not having a propper Diagnose... Besides L Rover are a rare sight in Mexico and in Work Shops and there is Not a single specialized shop for these cars , not even the LR Shops. ( only 2 in Mexico ).

I would slow down but itīs not really the speed , Itīs more the feeling that something is about to break or that the car is not safe or waiting for a major repair for something that could have been avoided.

I have a 1982 XJ6 ( Jaguar) with 28 K and cruise on that one at 100+ And feel like Im going slow ... Not really abnormal speedīs down here REALLY.

 

For the most part they would make noise all the time however, they could also be intermittent - its a guessing situation?????? A broken belt in a tire cannot be seen, you might be able to tell if the person balancing them can not get it to balance = spin tire, put on weights, its off again, repeat, repeat o thats close enough = broken belt. Lugs = I was referring to the heavy tread on mud tires - a big knot of rubber (tread) is also referred to as a lug.

"Iīm on the phone with work shop as we speak and told them about all your questions.. He said that Vibration is not constant or goes away inmidiately after resuming acceleration."

The above may, may point to the pinions - could be something is binding - let off it releases the pressure. As I said before its a guessing game without laying on the hands.

In basic terms about your speed

Sorry I didn't realize you are in Mexico, driving slower means you may be able to recover faster (at all) from some dork cutting you off and although it's basically safer to drive at slower speeds - you can't keep slowing down till your only doing 15 with the same problem chasing you.

Pinions - this is just a quick check and only tells you your bearing are shot, they can be loose and not move. Grab the driveshaft about four inches oops ten centimeters away from the differential and push it up and down 12 o'clock and 6 o'clock - while doing this LOOK at the part that goes into the diff - if it moving up and down excessively at a minimum your pinion needs looked at

Robert

 

Well Yes it does have that 12 , 6 o clock play , it moves about a quarter Inch up and down. Ill be checking these Pinions tomorrow with my shop. What should I be looking at?

 

When you remove the driveshaft you'll see a nut (if I remember correctly) that not only holds on the pinion flange (what the driveshaft bolts to) but it also holds correct tension of the pinion. This needs to be looked at by somebody with more experience than me, sometimes you can tighten (re-torque) the nut however if it moves to much it changes the mesh of the pinion to the ring (also called lash=mesh). as i said its hard to tell without seeing it - I am guessing. If the mesh is messed up it will destroy your ring and pinion set - it may be tough but someone really should look at it - all the things I mentioned are item I would check off on my vehicle but, I can walk outside and look at it, I stress this because a ring and pinion set is expensive and to properly set one up it should be blueprinted (a good shop).

Robert

 

I looked them Up on my Repair Manual , seems like a pretty straight forward non complicated or very repairable thing. right ? or at least not very expensive.

Could something in the transfer box or rear diff be causing the vibration other than the so called pinions?

 

ok have you looked at the xfer case out put shaft flange(were the drive shaft bolts to the xfer case ) it has a nut that does come undone and this will cause a drive line vibe ...

 

I put 3 bottles of Fixaflat on a rear tire on a work truck once so I could get home and it started to vibrate on the rear tire's when I decelerated? I would have never know what was wronge unless I had done it! Just my .02 cents good luck!