jenyap

I thought I'd share this: I replaced the K1 piston spring last weekend which fixed the 2-3 shift flare. It's a very easy fix, I highly recommend it to anyone struggling with a soft 2-3 shift on an auto. You can order the kit from a Mercedes dealer part# 1262704477. All that was required was a pan drop ( 6 bolts) and a screw driver. About 30 minutes from start ( fluid drain) to finish (fluid refill).

jenyap

My transmission pan is leaking fluid. I had it off to do a trans filter and K1 piston spring replacement. I couldn't figure out how to check the pan for straightness while I had it off since it has legs where the bolts go... Anyway, replaced the gasket, torqued to spec and it's leaking. Any ideas anyone? The car is a 1986.5 auto.

Landseer

I found the torque spec too low and wind them up more tightly.

The pan seems very well made and strong.

You don't have much to loose.

Sure its the pan? Which area(s) of the pan are wettest?



Thank you for the shift kit recommendation.
Is that K1 in the valve body?


I had a spare pan but shipped it, gratis, to somebody.

ROG100

We stock the spring for $10 if anyone needs them.

dr bob

Jenyap-

I'm convinced that the method for attaching the pan needs to include how you tighten the bolts. Because you are seating the rubber gasket, tighten the bolts by fingers only (socket OK but no handle or ratchet attached)until they are all finger tight with the pan up against the trans casting. Do this as evenly as you can. Try holding the pan up with one hand and tightening the bolts with the other until they just touch the pan. Once they are ther and even, tighten them in all in half-turn increments, and a diagonal pattern similar to what you would use on wheel lugs. So 1-4-2-5-3-6, for instance. Repeat this until you start clicking the torque wrench, continue slowly (smaller fraction of a turn) until they are all correct. This should eliminate the risk of squeezing the gasket unevenly, and of accidentally warping the pan.

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Even a cheap torque wrench is better than none. While the bargain Harbor Freight clickers may not be as as accurate as a Snap-On, for most jobs they are close enough. The big advantage of the torque wrench in this application is repeatability; all the bolts will be about the same tightness. For this application, you can probably afford the $20 for a 1/4"-drive clicker. Note that the pan bolt torque spec is very low in the range of most 3/8" torque wrenches, so a 1/4"-drive wrench is a much better choice.

Many folks have made it through their DIY auto lives tightening things by hand with no measurement. "That's not going anywhere!" is a common theme on suspension bolts and other big stuff, but is death on small bolts into aluminum while tryting to evenly squeeze a soft gasket or seal. Invest in a few sizes of torque wrench, and you'll likely find out that 95 lbs/ft for the wheel nuts isn't anywhere close to "That's not going anywhere!" tight. And that they will come off a lot easier and you'll risk fewer stuck, twisted, cracked or galled lug nuts and seats. And fewer leaking trans pan seals.

jenyap

I did tighten the bolts in very small increments. One thing I've noticed is that it didn't start leaking until it was tightened to spec. What I did was finger tight, fill with fluid, check for leaks (none were visible), torque to spec in very small increments. That's when it started to leak. I suspect that one or more of the protruding "legs" on the pan is too long or too short causing the pan to bend once torqued to spec... In summary: it did not leak when it was under-tightened, started leaking once was up to spec.

jenyap

Landseer, yes, the K1 spring is in the front of the valve body. All you need to replace it is remove 4 screws holding down the cover of the K1 spring and replace. It's so straightforward anyone could do it. You can see a writeup of the procedure here. http://www.benzworld.org/forums/w201...3-722-4-a.html

jacal128

Mine has the same flare between 2nd and 3rd, is it as simple as dropping the pan and swapping the spring pack. Tried filter and fluid change going to check the modulater pressure, but everything points to the K1 spring. Thanks, Jack