Vibration in the Middle

[TBzdega]

I have a 2003 Land Rover Discovery with 150,000 miles....just replaced the automatic transmission with a used one. After getting it back from the shop it gave a bunch of oxy sensor code which have been resolved...no more CELs...I now get an intermittent vibration in the seat?something like a wheel out of balance but not quite the same?is there something else I should look at??...thanks

 

[Quentin]

Could be a number of things, but what jumps to mind is the following:
Transmission mounts not refitted properly
Propshafts were not marked when they were removed and are now running out of balance.
Worn UJ

 

[TBzdega]

Thanks...that was my fear...several days of trial and error....until I find it

 

[rovercanus]

Could be a number of things, but what jumps to mind is the following:
Transmission mounts not refitted properly
Propshafts were not marked when they were removed and are now running out of balance.
Worn UJ

He didn't say they did the prop shafts. Why would that effect anything? They aren't balanced to the transmission or diffs.
You say a lot of stuff.

 

[discostew]

he also said at times . so describe those times for us / accel/decell/ one gear but not others ? I dont know about these other guys but I left my crystal ball at work

 

[TBzdega]

its probably the strangest vibration I have ever experienced and I have been around cars for 40 years?.its definitely coming from below rather than in the steering wheel like an unbalanced front tire. It's not linked to speed except to say it fluctuates at different speeds?my closest example would be like a bearing going out or a motor mount?.with a 150,000?this truck make a lot of weird sounds and isn't the smoothest runner?I am going to start with the tires and work my way through the bearing, mounts & axels?thanks for the help

 

[Quentin]

He didn't say they did the prop shafts. Why would that effect anything? They aren't balanced to the transmission or diffs.
You say a lot of stuff.

No they are not balanced to the diff or transfer box, but it is always good practice to reinstall the shaft in it's original position to maintain the "run-in" balance.

 

[discostew]

here are some things you can try to figure this thing out. when you get it to the point when you feel the vibration see if it still vibrates when you put the truck in nuetral and coast at the same speed if it does you have something goin on in the axles or prop shafts. If you figure out its at a specific rpm then see if you can duplicate it in park by just bringing the rpm to that level. if so then you are dealing with a flywheel or converter. or its going to be at a certain rpm in one gear but not another. chk those things out and let us know what you find.

 

[TBzdega]

I had the wheels balanced to eliminate them…..the vibration is like a low grade rumble which fluctuates in intensity but never severe enough to make you feel the car is undriveable. It comes and goes in intensity as you accelerate through the gears with 2000 to 2600 being the most noticeable RPMs….above that it mellows….when you coast in neutral the intensity diminishes but definitely does not go away. In park there is no vibration through to 3500 rpm….. This has been extremely helpful….thank you!

 

[discostew]

sometimes people adjust the park brake too tight and that causes a similar vibration especially on decel for some reason. Make sure all the prop shaft flanges look like they are torqued and not damaged in some way. Also a couple times I have fixed strange vibrations by removing the flywheel to torque converter bolts and indexing the converter to the flywheel 180 degrees. But do that as a last resort cause it really is a long shot.

 

[discostew]

I think I should have mentioned the tabs on your flywheel that trigger the crank sensor. its easy to bend those when you remove the torque converter bolts.

 

[terrormachine]

I think I should have mentioned the tabs on your flywheel that trigger the crank sensor. its easy to bend those when you remove the torque converter bolts.

It's a DII. Doesn't have tabs. But the flex plate could have been cracked if the mechanic involved decided to hammer the flywheel down to 300 ft lbs. with an impact.

 

[TBzdega]

My plan was to take care of the driveshafts as they have never been serviced or replaced. The vibration started about 6 days after the tranny was replaced. If the problem persists after I do the shafts and lets then assume we have an internal issue with the flywheel or converter...is there any risk in driving the truck…is it something only a shop could handle by having to remove the tranny and servicing it again?

 

[terrormachine]

Replacing the u joints with serviceable ones with zerk fittings is a good idea anyway. Too bad whoever replaced your tranny didn't recommend it.