Yes .10 mm not inches according to land rover, which is .004 of an inch or 4 marks on the dial gauge. TSB= Technical service bulletin. TC= Transfer Case.

 

You know after further review of my video, transfer case output flange is off by about .007 in. In spec is .004. The drive shaft flange is .001

 

That could be machining tolerances in the splines on the TC flange to TC shaft. 0.007 thou isn't a huge run out. It could also be concentric difference in the machining between the shaft theoretical center line and the outside of the flange. The truer test would be to redo the dial gauge test on the inside TC flange locating shoulder with the shaft flange unbolted and removed. Notably the shaft flange is only 0.001 thou eccentric which is located on the drive flange inner recess shoulder which suggests the drive flange is seating correctly and almost spot on concentric to the TC flange shoulder recess. My guess is that if you check the inner TC flange recess shoulder you may find that is more accurate. Also check the TC flange face for run out to see whether it's sitting square on the TC output shaft, if it is then no worries. Also worth a check would be the torque on the flange nut is correct. I always set the torque wrench at plus 5-10% over to allow for flex and rubbish torque wrenches. Uncalibrated torque wrenches vary enormously but fortunately I have a good industrial Swiss made torque wrench but even that isn't infallible. The digital torque indicators are around +- 3% tolerance as well. Good luck.

Sorry for the lengthy prose, I also struggle sometimes with some of the stateside spelling differences - not proper English you know

PS. I've ordered up all the engine and transmission mounts - all genuine OEM LR as I read on here and elsewhere that the after market mounts were a bit hit and miss on their quality. Next fun game will be fitting them

 

Well i had an extra transfer case flange from another, i just threw it on when for a drive, and same thing, my vibration is on acceleration only and around 40 mph and 75 mph. Its perfectly fine between 0-40 and 50-75 Ive had wheels rebalance 5 times, switched wheels with another set. The mounts made a large difference, but i think they just dampened some of the vibration. The only thing left i can think of is cv joints, half shafts or front diff. The hubs/bearings seem to be fine. I hate to start throwing parts at it.

 

Do you have access to a rolling road? If you can get onto one you may be able to isolate the problem whether it's front end or rear end vibes. If you sit in the truck on the rollers you can often get a 'feel' for whats going on and then watch closely (not too close though - I never trust those things under power) while someone else runs the truck on the rollers. It's a real head-scratcher though, I'll give it some more thought and do some web browsing over this side of the pond. The Aussie websites are also good for problem solving as they're big into LR's.

PS just an after thought, did this start after any parts replacement or engine engine rebuild? Not crankshaft/rods/pistons out of balance possibly, why I say is it's only on acceleration and not deceleration. Also the axle has an enormous harmonics counterweight attached to it for some strange reason, I often wonder why?

 

I've been experiencing almost the exact same 40-70ish mph vibrations. At first I thought I might have a loose bolt after replacing my front drive shaft, but I checked and they were all good. The vibration is a bit disconcerting, I almostq hear it as more of a grinding at some speeds but it doesn't seem to affect performance at all. How big of an endeavor is it to replace worn motor mounts? I don't have any close to level ground at my current place so jacking the truck up is always a bit terrifying.

 

You dont need to jack up the truck, mainly the motor. Probably a 2-4 hr job.