`94 Automatic Transmission Problems

[cornelius]

I own a 1994 XLT 4WD with 85K miles. There is a 3 to 5 second pause when shifting into R / OD, and I have to rev the engine a little to get it to go into gear. The pause is usually less when shifting into D. It is always worse when it is cold. Sometimes it will fall out of gear when coming to stops, or when moving slowly it will make a whirring noise and the rpms will increase, and will clunk into gear. When either happens, I have to stop, put it into park, then move it back into gear. These problems are alleviated for about three weeks when I add about 3/4 quart of transmission fluid. It does not, however, show signs of leaks (i.e. there is never any fluid in the driveway). I have to add fluid about once every month, as the problem starts up at that frequency. I helped a professional mechanic drain and replace the transmission fluid and filter at 75K. I complete all of my maintenance as close as possible to the schedule specified in my Haynes manual, and I always warm up my vehicle on cold mornings. I have tried adding fluid with "Stop Leak" but to no avail. The gear selector is not as tight as it used to be, with a little mal-alignment, but nothing too drastic (i.e. the selection needle points on the front of the letter D instead of in the middle). All of the transmission help sites I have read state that I should just continue to add fluid, and I will continue to do so, but I would rather repair the problem than keep janking it to work. I know very little about transmissions, but I do know a whirring noise is not good. I used to "throw it into gear," but I have since broken myself of this habit. Could this be a selector tensioning problem or an in-transit fluid leak, or does my transmission have severe problems? Any suggestions would be greatly appreciated.

Thanks,
Cornelius

 

[monsoon]

tranny fluid going somwhere?

exactly the same problem with mine? I have not found a good answer ---please email me if you get any insight.

thanks

 

[BUCHVILLEMAN]

im not too sure so im jus throwing this out but could it be the torque converter slipping. i know that Hank (of Flexplorers) had some issues recentlly and had a torque converter friction additive put in but im not sure.

 

[monsoon]

modulator change does not sound fun

I found this on the site mentioned-----

kinda makes me nervous to change the valve.

what do you guys think?


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just a recap and an update on my experience with changing the modulator valve on early model explorers.

I had lots of pinging and evidence of tranny fluid in the vacuum lines. Everything pointed to a modulator valve that was admitting tranny fluid into the vacuum system.

Changing the valve was a nightmare and all descriptions of the process fail to mention the short pin that mounts on the front of the valve. It's easy to lose and if you bend it you'll have to do the rounds of the local tranny shops trying to find a new one.

Once the new valve was installed there was a 'flare' or slipping between 2nd and 3rd and overdrive was gone. Also, there was no downshift.

The tranny shop reports that the unit needs to be torn down and may require a rebuild. They generally recommend NOT changing the modulator valves on geriatric units.

So if you have a very old truck consider keeping a close eye on the tranny fluid level and putting up with the pinging instead of changing the modulator valve. I expect the bill to be about $1200 CDN by the time I'm through with this.

Truck doesn't ping any more, though.