The Insanity Tour 2 - Trans Replacement Time
 

I've had my 300D Turbo for a little over a year now, the only real annoyance through the whole thing has been the trans. The PO or the PO's mechanic messed it up and I've been more or less waiting for it to die.

Which it did.

Once it knew that the jeep was down and I didn't have anything else to drive.

Jerk.

It went from "I'm a 4 speed trans that doesn't like the cold" to "I'm a one speed trans that doesn't like anything" over two days of city driving.

So today I have taken delivery of a shiny new(ish) freshly rebuilt 722.317 (and torque converter).

Now for the insanity tour part. The goal is to take the old one out friday, put the new one in saturday, and drive it to LA on sunday. With provision to drive to LA monday morning if needed.

So I come before the peachparts patrons to ask, are there any specialty tools I need to get my hands on before saturday at 6pm when I realize I need them? Any advice on removal and installation?

Get a 3' or 4' long, 3/8" extension and go in over the top of the transmission from the back side of the transmission to get to the upper transmission to block fasteners.

You're going to have to get that thing up pretty high to slip the tranny under. Most people use jack stands, but I prefer to use cribs...a lot safer!

http://www.peachparts.com/shopforum/...in-cribs-1.jpg

I've always pulled the engine when I've had to swap out the tranny so I can't give you specific guidance in doing it from underneath. You'll probably have to pull the driveshaft so a couple of large crescent wrenches or pliers to separate the two halves if you separate it. A transmission jack might be nice to have or help to balance it on a floor jack while lifting it in place. Make sure you get the torque converter fully seated or you'll damage the trans. Check the flex disk and trans mount while you're under there. Might also be a good time to replace the exhaust donuts while under there.

Good luck with the project and be safe.

as mentioned above, a 3-4' 3/8" extension (or enough to make 3-4' worth) to get the top two trans mount bolts. Reach up and try to break the bolts free with a 17mm box end before spinning them out with the extensions/socket combo.

outside of that, wax on wax off. i swap transmissions on these in about 2-3 hours, in and back out on the road. not sure why guys insist on pulling engines, these are easy.

also, do yourself a favor and replace the front pump oil seal on the trans. i wouldn't dare put in the trans without first replacing the seal

Thanks for the advice all, I hesitated to ask about other jobs while I'm in the area.

I have a trans jack, and no desire to pull the engine. I'll see if I can get a new trans mount, I did motor mounts earlier but haven't touched the trans.

What am I looking for on the flex plate?

Should I be worried about the front pump oil seal on a newly rebuilt trans from a company in high regard?

I've only done this once, but my memory tells me that there's something at the rear of the engine that needs to be removed so that the engine can tilt rearward without breaking it, ... plus the fan shroud. The engine is well balanced on the mounts without the transmission attached.

I have removed a couple, installed one, wasn't complicated but very heavy to hold up by hand, ... took me a while to recover from the muscle strain.

Rear tranny support can be removed to drop it down but if you are taking tranny out it should be out anyway.

Ok, car in the air, time for the fun.

First question. I see mention that I *should* replace the flex discs for the driveshaft, and I see some people saying I *need* to. Are they really one time use?

If it were me, I'd first go by their age- if they are 5 yrs old or older, replace them. If they are younger, check for cracks or other signs of distress. If all looks ok, reuse.

J.G.

No, they should be replaced when they start to show signs of cracking or other deterioration. You might be referring to the bolts/nuts, which some say are single use. It's a point of personal preference with the recommendation likely due to attorneys. I, for example, would never say publicly that I may have reused mine on occasion :D

Well I'll say publicly that I don't have time to care. Called the local MB dealer and the closest set is in LA and wouldn't get here until tuesday. None of the parts houses knew what I was talking about (big surprise).

They don't look that bad though, so I'm comfortable reusing them. I only had to pull three of the bolts to drop the shaft out of the way.

I don't say this often, so the 617 guys can get their fill now: I wish the 603 wasn't 6 cylinders, just a little bit shorter and I could tilt the trans down further.

There is the 602 or 605, ...

Pelican Parts is in Harbor City, and I usually get parts the next day being in So. Cal.

Ok, day two.

Got all the bellhousing bolts removed, finally. Started removing the trans but the torque converter doesn't want to come off the flex plate. It moves a little if I stick a pry bar in between it and the flex plate, but it doesn't want to come out with the trans. There isn't enough room to drop the trans out and then remove the torque converter. Any ideas?

And yes I removed the 6 torque converter bolts from the front of the flex plate.

You got to work with it. May need to turn engine over by hand and work your way around to separate.

Yeah, I ended up sticking a screwdriver up through the access holes in the bellhousing and in between the tc and flex plate, then used the whole trans to pry the thing loose.

Selfies with the ex:
https://pbs.twimg.com/media/CYToheKVAAAiCyB.jpg:large

Now to clean up in the tunnel a bit, then start tossing the new one in.

Any suggestions on fluid? I was dumping valvoline dex/merc (which meets dexIII) in the old one, but I didn't care that much.

What year is it? If it has some age on it I'd suggest sticking with dex/merc

New one is a total rebuild, book says dexIII so I'll stick with that.

Torque converter is filled and installed in the new trans. Took a while to get it to seat fully.

Ugh, new trans in, bolted up and hopefully happy.

Few more bits in the morning before I put the car on the ground and try to drive to LA.

Nice work!

Any Dex/Merc fluid that meets Dex 3 is OK. Maxlife ATF is very robust. I use it in several vehicles and it is wonderful. Full synthetic, so it can resist oxidation better. You might think about installing a stand alone trans cooler to keep this new trans cool and happy. In my opinion that's the best way in addition to 30k mile fluid changes to keep a trans in tip top shape.

It's nice to see another young ham here.

73

New shifter bushings?

I agree with synthetic ATF if you run it hard, better protection. Regardless, your choice meets Mercedes' minimum spec., so with proper maintenance it should outlast the car at this point.

New trans had new ones on the trans, I was missing all of them (surprise!) so I guess it's an improvement?

I'm gonna try and get my hands on new body side bushings, and a few other little bits I'm missing.

The original (as far as I can tell) trans went 356K, if I get the same out of the new one I'll be happy.:D

Clean and lube the linkage below the shift gate in the console and you'll really like the shifter!

Old trans had a rear output seal that leaked, entire underside of the car is 1/8" black slime. I had to wear full goggles while I was under there.

It's done. Got the final little bits in, linkages and hoses hooked up. Crossmembers back in and car on the ground. Filled it up and went for a drive around the block, filled it up again, adjust TV cable, went around the block, checked level, ran another errand, checked level.

HOLY **** THATS SOME GOOD STUFF.

On the highway I'm running almost 500 rpm LOWER than before for the same speed, shifts are smooth, firm, and quick. The pedal finally feels connected to the rear wheels. The trans engages immediately upon shifting.

To say the least, I'm a happy man. Ready for smiles per gallon going down to LA tonight.

Only thing I notice is that there's a whining/whirring now from what I assume is the TC, maybe it will calm down once it breaks in, maybe it wont. Honestly it drives so good I couldn't find a **** to give.

I'll try and do a little more detailed info once I'm on the other side of the state.

Congratulations big relief I'm sure and thanks for the explanation of full googles I had noted the outline on your face pictures.

Awesome,glad to hear it worked out good.

:2thumbsup

Haha,and just noticed you use the same mats I do when working under a car,they help a bunch to keep things clean.