I got a problem...

[jcabrera]

This is the problem with my 96 Disco 114K miles. In the AM with the engine cold, the transmission revs up to 4K RPM before it shifts from 2nd to 3rd. Once the engine has been running for a while, the transmission shifts fine. I check the fluids and seems in order. Any suggestion?

 

[Slam]

You can try cleaning the throttle sensor that is located within the top of the plenum. You will see the wires going into it (between the air intake and the plenum). Just remove the plenum with an allen wrench and pull it back to look inside. Inside you will be able to locate the sensor. Try to spray it off with some fast drying cleaner (like from a computer store or autozone). Then you have to reseal the plenum with some black silicone. It is not really that hard. Could take 20 minutes or so. That would be my first guess since a lot of times crap gets in the air vent and gets this dirty.

Good luck.

 

[jcabrera]

Slam, I will try this weekend.

 

[marc olivares]

jose,
if your engine rpm increases while your accel. pedal is depressed and the truck speed does not increase. this would indicate a transmission problem not and idle control issue. could you be more specific with your description.

 

[jcabrera]

The problem only occurs, I presume, when the transmission is cold. I let the engine reach normal operating temperature and it does not appear to affect the problem. The Disco accelerates fine, it shifts from 1st to 2nd but then, the RPM reaches almost 4K RPM before it shifts from 2nd to 3rd, with a very abrupt shift. After driving for about 5 minutest, the transmission shifts just fine, like nothing ever happened.

 

[VTVV]

Torque convertor, maybe?

 

[discomike]

Jose,
You didn't believe me when I suggested flushing your tranny even though you just did a service on it, HUMM.
Trust me on this, if your lucky a flush will remove enough lacquer and varnish as well as soften up the seals in the valve body. If it has gone too far you are looking at a rebuild coming up. Do the flush and try to get your pressures up.
Mike J.

 

[jcabrera]

Hey Mike, small world isn't it? I am planing on changing the fluid this weekend to hopefully resolve the problem. Did you get my post on socalrovers about meeting on Tuesday? shoot me an email, would be nice to see you.

 

[discomike]

Jose,
Changing the fluid will only remove about half of the fluid and none of the lacquers and varnish, go for a full flush with chemical cleaner, I really believe this is going to be your only cure other than a rebuild.
I'll get back to you this weekend.
Mike J.

 

[marc olivares]

i agree with mike,
take it to a shop and have a flush machine purge all of the fluid.
replacing with synthetic fluid will also raise the fluid break down temp considerably, although, i'm thinking in your case your looking at an overhaul.