tranny questions - PeachParts Mercedes-Benz Forum

md21722 · #1 10-22-2002, 02:13 PM

Two questions for '87 300D tranny 261Kmi....

(1) when in drive, stopped on an up-hill, if I take my foot off the brake, the car will roll backward... Is this correctable, or does it require a new tranny?

(2) when I rotate the driveshaft by hand, back and forth, there is a klunk that comes from the tranny. mechanic promises me it is the tranny and not the driveshaft. holding the two halves of the driveshaft and rotating against each other makes a much, much smaller noise, so I believe he's right. Is this correctable, or does it require a new tranny?

Thanks,
Brian

dpetryk · #2 10-22-2002, 02:21 PM

The roll backwards is done in the torque converter. There is a one way sprag that only allows the driven shaft into the tranny to rotate in one direction. So I would suspect that the problem is there.

The clunk sounds like there is a lot of play in the tranny gears. Some amount is normal but how much I am not sure of.

joe p · #3 10-22-2002, 04:42 PM

Two questions for '87 300D tranny 261Kmi....

Ok, with this mileage yep, it'll clunk unloaded but, its not a concern worth attempting to repair without a overhaul.

As far as rolling back on incline, odds are the converter is worn and the working pressure is low due to age and mileage, there again, unless your overhauling I'd be inclined to let it be.

Your at or around the design limit mileage on these (not my words, MB tech training words) and more or less anything extra you get is gravy.

Personal opinion, drive it and enjoy the fact that unlike many of its 4 wheeled brothers, your Benz has one of the finest designed, longest lasting auto's out there. When it expires, overhaul it or replace it with a reman unit however be prepared for sticker shock on the converter pricing.

Joe

md21722 · #4 10-22-2002, 07:48 PM

Thanks for the great responses so far. What is the next way the trannywill shows signs of its age? Currently there is no slipping out of gears, and it shifts all gears. However, the are various vibrations. I'm going to replace the center support mount and bearing and see if that helps. All of these vibrations are felt in the gas pedal, steering at speeds > 60MPH. At 77 the car has a different feel and has thru several sets of tires and other suspension work (to fix other problems) so I pretty sure its either the tranny or driveshaft. It seems shifting out 'D' into '3' makes the ride smoother at mosts speeds (not as effective at 77) which makes me think its tranny related.

I have another tranny and TC in a car with 175Kmi (part car, hasn't been run in 2 yrs, tranny known to work well). Is it worth pulling this tranny or is likely past its time as well? What about the TC? Mix and match?

Thanks,
Brian