Hi Everyone,

Original owner of 97 Disco I Auto 185.000 Mi. She now has acutely developed a low speed shutter and vibration at 30 MPH. Also have a "CLUNK" when shifting from Drive to Reverse, Which has been there for years. Only vibrates under load. No vibration/shutter coasting down hill in drive or neutral. Engaging diff lock no change in vibration.

Change out Rotofex joint. Took car to local oil lube shop and had all grease fitting greased. Checked rear diff fluid and it was full. Lube Guy could not check transfer box but said it looked good with no obvious leaks.

Still have shutter and vibration at 30 MPH.

Whats next to check/replace? ATF fluid/filter change maybe? Check front drive shaft?

Is the "clunk" an omen to AT failure?

Need some guidance. Hoping to keep it running.

Thanks in advice,

John

 

Check the front shaft, if you feel any play in the u-joints replace, same with rear's u-joint. Check the engine mounts/trans mount.

 

Panhard rod bushes and hub bearing/ swivel housing pre-load should also be checked.

 

Well Local Land Rover Knowledgeable Independent Mechanic says it's the Transfer Case. He basis this on the rover making a loud clunk when you turn the wheels Left or Right but is OK going straight... something about the viscus coupler?... Anyway given the age and miles he recommends trying to find a used TC over investing in rebuild. He would charge about 600+ for labor and fluids to install.

He also recommends to first service the TC and replace the fluid. Drive for a few weeks and see what happens.

Reasonable Plan?

 

There is no viscous unit in a Discovery, the transfer case is not affected by wheels turning so he is full of crap.

 

I agree the diagnosis here is either faulty or misunderstood. The Discovery 1 and 2 never had viscous couplings in the transfercases. That was the Range Rover that had that. I also agree the transfercase is not affected by steering/turning.

I second the suggestion to check rubber panhard rod bushings to diagnose a low frequency shutter. To diagnose the clunking or a vibration, check the u-joints as suggested, also the cv joints. Raise the front, steer left and right and turn the wheels to check front shaft play and any issues with the cv joints.

Clunking could also be just a harsh unloading of the drivetrain. I've found that if my transmission kick-down cable is adjusted so that it downshifts under less throttle/load, then it also tends to upshift more when the throttle is let off. Those throttle-off upshifts unload the drivetrain and it clunks. My solution has been to ease off the gas smoothly instead of just letting the throttle snap closed. I also conceded to a kickdown cable adjustment that requires a little more throttle to force a downshift. In any event, you could check your cable adjustment.

 

You have covered the points i was going to add but trying to stuff in breakfast before racing kids to school, also check all the rear bushes and A frame ball joint as these clunk when worn.

 

Thanks for the reply.... After getting your input I defiantly believe this Mechanic does not understand the D1 drive train. I ask him about checking U-Joints and he said the D1 does not have them? Kept talking about the Roto Flex which I already replaced. Anyway I am going to let him service the TC and then I will take Her to Dealership for a 1 hour inspection and have them look at every thing you all brought to my attention. I don't now how we could of broken that huge TC. This Disco was a Mom's Soccer car and has never really been off road. I work in a Hospital and it did help me get to work in D.C. through some very big snow storms when we lived in Northern Va. That's why she is a Keeper

Thanks for having my back

John

 

>>Clunking could also be just a harsh unloading of the drivetrain.<<

Yes the Clunk is very loud when backing up and turn the wheel sharply to the right. Feels like the Drive train is lifting up then loud "CLUNK" when you put in drive and go forward.

 

Have the engine/ trans mounts been checked ?