Replacing 4-Spd Manual Using Harbor Freight Transmission jack
 

April of 09 I did the 4-spd transmission swap in my 85 300D. I had the usual vibrations I read about others had with their swaps. tried to raise the trans mount, lower the X mount some, even lowered the center support bearing. been up and down with this thing. tried different transmission mounts, 300D, 240D etc...

Replaced the center support bearing and U-Joint. Just finished up on the rear sub frame and trailing arm replacement. swapped out lower milage trailing arms to eliminate the bearing problem. the R/R seemed to be complaining some. and swapped out a lower milage Diff from another 85. even new axles.

The FW was matched balanced also.

Driving around town, usually in 3rd gear, so the rpm`s drop in the 2000 range +-. so really get the roughness. on the highway around here, the speed is around 50mph, so have to be in 3rd to keep the r`s up.
with the 2:88 diff being higher geared than the 3:07, might be some of the issue. overall Iam happy with the swap. milage has gone up 3mpg on the Hwy.

so as time has gone on now, I have come to the conclusion it could be in the transmission. 1st and second is smooth, even running it up to say 3200rpm`s.
the 3rd there is a roughness in the drive train almost like a U-Joint. best I can come up with. then 4th also has it until Iam over 2700 to 3000rpm`s.

Iam starting to think maybe 3&4 have an internal problem like a bearing that has enough wear, that it letting the gears drop and not mesh correctly.

so I have another JY 4-spd Iam putting back in today. I pulled everything out on Monday, and yesterday I picked up a Harbor Freight Transmission Jack. the 450lb one with the 4 casters. SKU# 39178. it is Normaly $99, now on sale for $79, and with a 20% off coupon drops another $16 for a total of $69.59.

Have any of you used this Jack? Iam hoping today it all goes back in w/o any new words invented :D. I will report back as how well it goes back in.

When I did the swap, I pulled the engine and trans as a unit. so installing the 4-spd was a snap on the ground. I have pulled a few at PNP, just not replaced one laying on the ground.


Charlie

I bet you will have no problems, especially with a light weight 4-speed at under 100 lbs.

Thats like using a flatbed to move a TV. :D

I haven't got far enough along to R&R a MB manual transmission. But I'm friends with a girl who likes to kill transmissions in her Toyota truck. I've R&R 2 transmissions in the last 6 months for her :no:
without any oil in the transmission its pretty light. I just bribed a friend with beer and had him help me with lifting it into place... I wish I had one of those transmission jacks your talking about, would make it a 1 man job with no safety issues. Let me know how it works. ;)

On the issue of lightness, heres a picture of me holding one of the old iron boxes above my head. :cool:

http://i131.photobucket.com/albums/p...a65b2f1b16.jpg

I have one of those jacks. Works well enough I guess. It is designed so you can strap the transmission to the jack but in reality that does not work. You have to have the car up pretty high on jackstands FYI.

Goodluck

A friend at work just used one to change the clutch in a 4WD Toyota pickup. He said it was well worth the money.

Charlie,
That jack will be fine. I used your standard floor jack by myself but it was a balancing act. The platform on the jack you bought should work well.

Thanks for all the kind words and encouagement.

Here is a link to the jack.
http://www.harborfreight.com/450-lb-capacity-transmission-jack-39178.html

Well it looks like the car, 1 point, and me 0 zero for today.

Bolted the casters on the jack, swaped the trans flex disc from the old trans. the new one was pretty well cracked and had strings sticking out.

Figured it was easier to add the oil while it is on the ground than under the car. so filled it up.
Cleaned off the splines, polished up the end that goes into the pilot bearing, and greased her up.
Slid on the throw out bearing and the shift fork lever thing.

Got her straped down, then realized I needed to jack the car higher. needs to be more than 21". that is to the top of the trans on the jack. so fiddled with that looking for 4x6 to get her up.

Started raising her up. got it up in the tunnel, and realized, there is no way to undo the ratchet strap. can`t swing it in the tunell, so dropped it down and removed the ratchet, and tied the strap best i could.

Raised her back up. I left the slave cylinder attached to the line, so raising the trans you have to guide the line over the top and make sure it doesn`t get tweeked.

Raised and lowered the angle of the eng and trans trying to get he right angle. I could get the shaft in somewhat. but wouldn`t slide in. turned the end of the trans in gear trying to fine tune the splines.
Finally, removed the jack and man handled it. damn it was close, but no go.

Pulled it back down, to check the clutch and trans splines. felt something inside the clutch hole, wt....? I guess when i pulled the trans out, the pilot bearing came out. probably because I tiped it before it was clear. so here I was fighting this damed thing which seemed for ever. should have slid right in.

So in the morning I`ll see if a socket on an extention will fit into the hole and drive the pilot back in. Or just remove the clutch and see what`s up.

I did notice oil leaking around one of the shift levers. I think there is an "O" ring for a seal. I`ll checkin my stash of new rings, but probably some special MB specific thing. we`ll see.

Was a real nice day after 10am when the fog moved out. had to quit this afternoon about 4pm, wind came up and the fog came back in. too dang cold.

One thing I noticed with the metal plate the trans sits on, is it is slipery and the trans will move. I was thinking of bolting on a piece of plywood. the 2 ears on the bottom of the trans the exhaust hanger bolts on to, slip around on the plate, not much room on either side of them and they want to slide off.


Charlie

I just man handle the trans in and out. Are you using the 240d auto mount?

... A motorcycle jack works great for this.
it's flat, has wide surface to hold the trans on, and has rubber feet to keep the thing still.

Do like Chuck Norris and unbolt the transmission using your fingertips, then just lift the car off it with your other arm - leaving the tranny on the ground.

Easy.

no no no... Chuck norris would kick the bumper, then spin around and kick the other bumper, and the transmission would jump out, repair itself and jump back in.

the incredible hulk would unbolt it with his fingertips, and lift the car off the transmission leaving it on the ground...
or would he eat the transmssion? "puny automatic"

This is how I do it, doesnt everyone?

Yeah Iam using the 24D auto mount. I could man handle it better if I was 25 years younger :rolleyes:.

Where is this Chuck Norris when I need him? even the Govenator.

Charlie

Then I can assume that you have balanced the ds as well. Have you lowered the rear? You should check out the w124 FSM on the propeller shaft section. They cover DS related hums and fixes as well as measuring angle of inclination on the DS. It may give you some inside on your issues.

I could wrestle the trans onto the 616 without a jack, but when I tried that with the 617, she put up a fight. Left a pretty bad bruise on my left shoulder. There's not nearly enough room, I used a floor jack and a piece of wood, and I think I might want a trans jack for when I do the clutch.