tight vacuum, transmission slipping, no spring chicken, but still my baby - PeachParts Mercedes-Benz Forum

plutonian · #1 03-05-2010, 12:34 PM

1982 300TD wagon
Am I flogging a dead horse?
It's slipping really bad when cold at this point, but seems to motor along just fine when warm. Took it to a mechanic last month who worked on vacuum (±$450) before diagnosing tranny death. (says there'd have been no other way to come to that conclusion and I had to bite that). He offered to trade me a 1990 Volvo wagon that he's put a bunch of work into and I guess would be a a steal for the $200 he's asking along with my merc! Love my merc, volvo's are OK I guess, but it would cost at the very least, my last 2k, and quite likely twice that - or I could hang on to beast and find another old beater meanwhile - engine's strong, probaly about 350k on the clock (stopped at 255k) new rear axles, fat new tires, etc., probably put around $1500 into it each year for the last 4.
any thoughts !? I guess the volvo is a no brainer, but maybe I'm missing something

rrgrassi · #2 03-05-2010, 01:01 PM

Get the tranny rebuilt and keep it on the road. The MB is a way better car than the Volvo, IMHO.

BoiseBenz · #3 03-05-2010, 01:32 PM

Many of these old 722.3xx trannys (like you have) are prematurely diagnosed as dead. With your assumed 350k, I can't imagine it's original; if it's been replaced (at, say, 200-250k), it should have a while to go yet.

Please keep more detailed notes than the generic "slipping when cold." "Reverse always OK but slips IN GEAR when started from cold from 40 dF until needle is up to about 60 dC" or "Slips on 2-3 shift" etc will help to determine if it's a guts problem (clutches or bands) or an external problem (need new B2 actuating rod or seal, low level, clogged filter, needs shift kit, etc).

The sweet ATSG book from bulkpart dot com is a nice read.

rs899 · #4 03-06-2010, 07:17 AM

Quote:

I can't imagine it's original; if it's been replaced (at, say, 200-250k), it should have a while to go yet.

What he said, except who knows what it was replaced with when or if it was replaced. Perhaps the PO or PPO replaced it with a junkyard unit that only had a half-life left on it. If you like the car (and you seem to) and you have been dumping ...er ...putting $1500/yr into it , whats another $2K? Or do it yourself if you have the time, and it truly needs an overhaul.

Rick

layback40 · #5 03-06-2010, 08:18 AM

Slipping when cold sounds like a clutch pack problem. Especially if its been slipping for a while. If it was me, I would find a good second hand trans and put it in.
I have the above mentioned book, it is a good read. I think the trans could be original & just ready to be replaced. Maybe you have been spending too much on the MB on the wrong things. TD's are hard to come by, especially if its a good sound one.
I dont think much of volvos.
See if you can get a low mileage trans out of a write off. Some one on here may have one.
Sounds like your mech has already extracted plenty from you.
It doesnt take $450 to diagnose a bad trans!

leathermang · #6 03-06-2010, 08:19 AM

search Trans-X in the archives... in case it is caused by varnish build up in the little holes in the trans valve body... the bb size and shaped anti flow balls work with gravity and does not take much varnish to cause them to stick as a result... a $20 try which has helped many...but does no harm if it does not work... I am figuring two cans in that cost estimate... follow can directions... one percentage for initial cleanout , less for leaving full time after cleanout...

plutonian · #7 03-07-2010, 08:59 PM

Hm. Thank you for the input.
Seems all the mechanics worth their salt in this area (Monterey, CA) charge ±$100/hour so gets expensive pretty quick!
Had a look around for a used transmission, but nothing so far.
Not sure what the range of years and models with same transmission I can be looking for is though either.

Yes, remains strong in reverse, but before warmed up, the engine revs with very little drive in D, S or L until I've crawled around on level ground enough to warm it up before hitting the highway. Tachometer is kaput, but at this stage, it's slipping at low revs regardless. Once warm though, there is no slip and gears shift comfortably.
Just moved from the top of a hill where I cruised down to leave, to a place down in canyon where I have to climb steeply to get out and the problem has increased rapidly from having to make a couple of runs at the hill to get out (would make it half way, engine revving, but vehicle slowing to stop and starting to roll back, engine still revving if I kept foot on gas, so I'd quickly back up a way, idle a little and try again!) to now leaving it parked a mile away at top of hill. Don't think I'd make it out again now!
Had similar symptoms a couple of years ago that seemed simply to require topping up trans fluid. Not the case this time and it's degraded fast in present conditions.
I'm sort of at the end of my financial tether actually and not sure I can even cover the costs of having the job done and think it's way beyond my means to do it myself - between a rock and a hard place. Not crazy 'bout that Volvo either, but I know the dude's put a grand in parts into it and it'll be sound for $200. I don't know....

MBZ123 · #8 03-08-2010, 01:42 AM

Quote:

Originally Posted by plutonian

Had similar symptoms a couple of years ago that seemed simply to require topping up trans fluid. Not the case this time and it's degraded fast in present conditions.

You're absolutely sure bout the fluid level? It's got the correct dipstick too right? Sounds too similar to symptoms of having low fluid. Pray that hasn't already caused irreparable damage. You've done the shifting down to lower gears routine? Not privvy to any previous threads so this may be moot. A boneyard tranny will only set you back 125 or so, but you sound convinced about that volver. Of course we're all biased here, but imo that thing has 0 character no matter how much $ you dump into it.

FNHB

10fords · #9 03-08-2010, 10:15 AM

X2 on the check the fluid level or just add a quart for the heck of it and see what happens. There seems to be a real art to properly reading the fluid level on the dipstick. I get different readings all the time and sometimes I just can't tell what the level is. If you need a hand PM me- I'm just over the hill from you and I may have a good trans if thats what you need. I would hate to see you have to drive a Volvo!!

MBZ123 · #10 03-08-2010, 11:59 AM

Quote:

Originally Posted by 10fords

or just add a quart for the heck of it and see what happens. There seems to be a real art to properly reading the fluid level on the dipstick.

I would hate to see you have to drive a Volvo!!

What he said.
Fluid level in her tranny seems more moody than most my ex-gfs.

FNHB

plutonian · #11 03-08-2010, 01:24 PM

thanks for the empathy re the volvo. It would appear to be the easiest path to staying mobile for least cash outlay, but you guys are killing me, and the reason I do drive a MB needs no explanation here. (It's actually the only non 4x4 on these dirt roads!)

I understood overfilling tranny fluid can cause some sort of damage, but I guess it couldn't really hurt in this case so I'll try that and maybe start looking around for another set of wheels to tide me over while I look for another tranny and someone to switch them out...

dadette123 · #12 03-08-2010, 02:45 PM

Quote:

Originally Posted by plutonian

Not crazy 'bout that Volvo either, but I know the dude's put a grand in parts into it and it'll be sound for $200. I don't know....

Like others here, would hate for you to trade your beloved MB for a Volvo. BUT, if you do and since the seller is the mechanic who fixed it up, I would negotiate a really sweet "stand by my work" warranty for at least the first year. If he doesn't want to then you just may be trading one known problem for the unknown.

plutonian · #13 03-11-2010, 10:03 PM

Sequence of events:
Transmission appears to be slipping
Check fluid - it's high
Take it to the shop - they do a bunch of work on vacuum
Get it home - barely get out my steep drive again.
Get it back to the shop - they say needs new transmission
Get it home - check forum, write this post - advised to dump a bunch of fluid in the tranny anyway - I check it - its empty!?
How'd the hell that happen?
And why would the mechanic tell me I need a new transmission - cos it's running just fine now! Thank you guys.
Moral of the story?
Don't forget to cross check the obvious perhaps? Still not sure what happened to the fluid between my place and the mechanics' (apart from two weeks passing by and I'm not seeing any signs of a leak so far.)

MBZ123 · #14 03-17-2010, 06:22 PM

Quote:

Originally Posted by plutonian

How'd the hell that happen?

Exactly the same in my case. It seems to happen with no rhyme or reason, ergo, my "moody" reference in earlier post. I just stay on top of it. One thing I am almost 100% on is the front seal is going bad or already there as its the only spot left where fluid can be coming from and almost impossible to see up in there. Only theory I can muster at this point re: extreme volume loss vs. minimal loss is that some trips will see it leaking profusely while out and about and some won't. I can only verify what drips when its parked. Frustrating is an understatement.

FNHB

plutonian · #15 05-12-2011, 02:07 PM

over a year gone by (only about 40 mile round trip to town twice a week) but the thing just keeps on trucking!
Found that so long as I let the engine idle for 20 mins before attempting to drive, it'll tractor up the steepest hill with no problem. However, trying to drive with a cold engine even on level ground requires me to start in 1st. There is also a lot more "searching" between 2nd and 3rd on any grade. Guessing my lucks gonna run out soon, but man, these things were built to last.