it's worth a shot! pull the shaft, and replace em, drain the oil, and change it to rotella 5w40 then change the filter! if it's not up to 3 on cold idle, I'd pull the sender, and put a true gauge on there, and see what it's doing.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!