Transmission issues -slipping out of forth
 

I live in upstate NY in the Catskills and need some transmission help regarding the Bowden cable. One of the gurus on this site (Hunter) told me it is probably the bowden cable but I have been under the car checking it out and don't know where to go from here.
The car will not stay in forth gear until I have run it for 1/2 hour or more and sometimes won't ever! I manually have to move the shifter to forth to get it to go and most of the time it just slips into neutral. Once in a while it will catch but only after it is warmed up.
I have disconnected the downshift switch under the gas pedal and it still won't get in forth. The Bowden cable seems connected well at the linkage. Now that the weather is warm I would like to get under there and figure this out.
Any help would be appreciated. If anyone is close by I would be happy work out a trade or pay for some guidance. My brother owns an organic butcher shop, I work in architecture just in case anyone is into bardering.
Please help
82 300sd 100,000 miles (tranny help)
85 300td 240,00 on odometer but its broken (no odometer, spedo, and very hard brakes)
87 300sdl 300,00 miles (broken sunroof, leaky windsheild)

Firstly, you failed to specify the vehicle in question.

Secondly, there is no possibility of moving the shifter to "fourth". When the shifter is in "D", it offers you four gears. Please explain, precisely, how the shifter allows you to access fourth.

When the shifter won't allow fourth, what's the engine speed at 60 mph on the highway?

tranny help
 

Sorry, the 82 300sd (tranny help) is the one.
When I am accelerating from a stopped position in drive it cycles up through the gears and when it tries to get into forth it slips out and just revs. What I have done in the past in put in into 3 and then shift it up into D to get it in 4th.
I can't tell you the RPM because my tach doesn't work, but it is reving high.
Any thoughts?

You're describing a "flare". The transmission revs up between gears and shifts when you lift your right foot.

Is this correct?

Tranny
 

I don't know if I am using the proper terminology but the car will not get into in forth gear. It feels like it goes straight from third gear into neutral instead of forth. On the rare occasion when it is good and warmed up it will get into forth. Is that a flare or slip? And any good thoughts on how to fix?

What happens when it goes into neutral and you lift your foot?

Does it stay in neutral...........does it fall back into third?

Are you coasting without any power?

Details..............the devil is in the details.

It just revs back down to idle when I lift my foot, it does not go back into third. It would coast to a stop but I usually shift back into third gear.
Feels like we are getting closer.

I don't have a lot of hope for that situation. However, you can disconnect and plug the line to the transmission modulator (from the vacuum control valve) and see if the problem is eliminated without vacuum.

If the vacuum tip doesn't work then what is the diagnosis? Bad tranny?
The power locks don't work so maybe it is related. Any ideas of how to proceed if it does shift correctly with no vacuum?
So you don't think it has to do with the Bowden cable after all?
Do you know how to tell if that cable isn't hooked up correctly? If so then how?
Sorry if this is way no many questions.
Thanks for your help though!

You currently have a "bad tranny".

My attempt is to methodically work towards a solution..........inexpensive, if at all possible.

You might prefer to ponder all kinds of possibilities...........I generally work one step at a time and attempt to gather data at each step.

Answering e-mail
 

You need hands-on local help.
Good MB Shops
http://www.peachparts.com/shopforum/good-mb-shops/

My least expensive guesses in order of cost, cheap to high:
* The vacuum modulator is junk
* The valve body springs are weak/damaged
* Valve body gummed/sticking pistons
* Bad valve body
* Burnt clutch pack/damaged band
* Major transmission damage



Have a great day.