I've got a 1990 245 with 195k miles on it. Recently I've noticed it driving very sluggishly. Like the tires were extremly low on air (their not). When I let off on the gas it slows down immediately, like a brake caliper is dragging. None are, I jacked it up and spun the tires, no brakes dragging.
And I've noticed a small drop in milage has happend. Engine oil and transmission (Auto) has been recently canged. I'm going to change the differential fluid as soon as it warms up a bit. Could this be the problem, it's never been changed as long as ive owned it. Two years.
Any ideas? I'm at a loss.
Thanks
Andrew

Come to think of it, if it was my car the first thing I would do is check the condition of my air filter. If clogged, it would cause sluggishness and lower MPG.

BTW - I wouldn't worry about your diff. The differentials in 240's are almost indestructible. I've never heard of one going south. No fluid might be the only way to destroy them. I'd do a finger check now and then change it later as you mentioned in your post.


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90 244DL about 1/4 million miles - original engine/drivetrain :)

I've got an 85 and maintaing 60 on the highway was a chore, I was thinking fuel filter, amm, and everything else that a brick owner has go through thier head when something doesn't feel right. luck has it that I started hearing a vibration underneath and it was the transmission mount had fallen apart. After replacing the old with the new and letting the tranny down off the jack there was a sizable difference in the alignment of the drive shaft and the green monster now drives %75 better, especially on the higway. I can now cruise at 70 without working the gas pedal.

Start with the small stuff....

Cold weather might cause a small loss in mileage, but not the sluggishness. You didn't mention tune up. Have you done that recently? Or at least checked plugs, cap, rotor etc.


Onto the bigger stuff...

A bad O2 sensor or clogged cat might explain your problems.




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90 244DL about 1/4 million miles - original engine/drivetrain :)

Or if there is any oil in the diff! Probably a good idea to change it.

What is causing the trouble?

Other than an exhaust restriction or loss of oil in rear-end (or loss of fluid from "fresh" change in tranny??) Was the tranny change done properly?

Sudden changes lead one to suspect the last thing "fiddled" with on the car.

If the change was not sudden so much as recently noted then it may just be tune-up time.

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Mike!