'99 LX470 "shudder"

[erupert]

Didn't get any responses on the Lexus Owners forum so maybe the Toyota forum has more viewers.

I have a '99 LX470 that I have owned from new. It's had all the required services through the Lexus Dealer through the 60K major which was done at the Toyota Dealer. After that, all minors done by me in my friends shop and the 90K major also done at the Toyota Dealer.

Around 98K, there would be an occasional "shudder" when accelerating from a dead stop with the front wheels turned. With 118K now, it's pretty much constant. The shudder is very short in duration.

I am thinking that because it happens only with the wheels turned, it's related to the AWD system. I heard that Jeeps with AWD had this problem related to the viscous clutch in the transfer case.

Looking to fix this problem if I can. Anyone else experience this? Thoughts about a strategy? I found that even though I paid a dealer top $ for service, they never greased the driveshafts. I have greased these but is has had no effect. I am also wondering about switching the diff fluid again and maybe using something like a Red Line made for LSD's.

[erupert]

In case anyone else runs into this problem, I'll post - The STUPID dealer put non-LSD fluid in the rear. After going around with them and they suggesting that I need a new rear, I decided (since it started after they did the 90K maint) to swap the fluid myself. The prob went away immediately. I spoke to the dealer and they graciously donated 100% of the labor on the timing belt change at 120K.