I think I may have a trans problem
 

because it shifts very hard. When the A/C is off and I am in the throttle pretty good, the tires will break loose going from 1st to 2nd. They make a very noticeable chirping sound just like my old chevy truck with a 350 and a shift kit used to do. I was very surprised that the car has enough power to do this. Is there one main component that could cause this or do I need to get out the Mityvac and get to work? Thanks!

I would look at the vacuumn line going to the modulator first.:) And then backtrack from there.

You note that this happens when the A/C is off. What happens when it's on?

So far it sounds like a vacuum problem. Leaks can be a pain to track down but they're certainly preferable to a shot tranny.

Check vac' to trans as modified by the i/p mounted control valve.
By shortening the operating rod some, softer shift with no flair should result as long as there's above 8 inches of vac'.

Usually the edge of the bell crank should be half way through it's travel and have 5 inches of vac'.

More vac' signal there is, the softer the shift should be....up to a point.
if it then flairs between gears, you need to reset modulated line pressure.

Unfortunatley, the gear shift shock loading will break stuff inside the trans'....and then it's a trans' out repair...fix it now.:)



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Only reason i said A/C is because with it on, it draws enough power where trans wont shift hard enough to break loose the tires. It still shifts very hard even if the a/c is on. Thanks for the replies

Ok. The only reason I asked is because I have a leak in my climate control system somewhere that causes hard shifts. With defrost or the button next to it depressed, it shifts perfectly. With any other button depressed, including 'off,' it shifts harder. I've read that a restrictor is supposed to prevent this sort of thing from happening...but not on my car, evidently.

Thanks for the info. I will run my CCU through the cycles and see if it makes a difference. Gotta love all of the info on here! Amazing!

JEREMYC, I don't recall seeing how long you have had...
 

your MBZ but if you don't already have a hand vacuum tester [pump and gauge] it would be wise to invest in one [ ~$40-$60 ] ... "MityVac" is one of the brands/models many on this FORUM have. This will prove most useful in diagnosing and solving the many vacuum issues you WILL FACE while owning these vintage diesel cars.

Specifically addressing your tranny issue, I would "T" off in the engine compartment from the vacuum line that runs down to the tranny and see what vacuum profile you have there... both while sitting with the engine running and then while driving the car. If you could do this and then post the results, you might be surprised at the number of people here that can chime in and advise you.

I'm on the road just now and will NOT have access to the FORUM regularly.

Best of Luck,

Sam

I'm beginning to think we need a sticky in large, bold letters for this link:http://articles.mbz.org/transmission/adjust/

(Search function I'm sure would bring up a mention of it at least.)

Would this mityvac do the trick? Price seems right if it has the accessories I need to test various components.
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=39522

The transmission would prefer this sharp shift since there is less slippage / wear on the clutches. This said, it can wreak havoc on the rest of the driveline.

i think i got the same one at autozone for $5 less, but yes ,it will do fine.

Let's not forget... ... and mobetta... I think
 

Well "pardner" let's not forget:
http://www.continentalimports.com/ser_ic60442.html

mobetta,
I think the pump you are looking at is all plastic... and if so I would recommend you look for one that is metal and thus will likely last longer!?
Sam

Thanks Sam, I definitely want an aluminum housed pump.

I think I paid ~$45 for my MightyVac look-a-like...
 

and it had a nice heavy brass pump cylinder... but still it was made in China!
Sam