Help with my transmission! I am new!

[HHaisten]

I have owned a Grand Cherokee for a year.
This past weekend, I bought a 1988 Jeep Comanche 4x4 (4.0 inline 6) Laredo with 130,000 miles on it. This will be my hunting vehicle.

The engine is sound--starts good, idles good, runs strong. there is only one problem with the truck. Every once in a while, the transmission will slip going into second. Right as it is about to shift, the RPMs shoot up,and it slips. It only happens sometimes. I don't know how the transmission has been maintained over the years.

Any suggestions, or ideas as to what this could be--minor problem or serious??

thanks

 

[Tug-n-pull]

YJ wipers on a CJ?

Welcome! Do you know what transmission you have? tug

 

[HHaisten]

not sure. 1988 4.0 inline 6. I have been told those are Toyota transmissions

 

[Bounty__Hunter]

5speed or auto?

 

[MudderChuck]

Spring over lift?

If it´s an auto, it´s most likely the AW4. I´d change the trans oil to Dexron III. This may take two changes a few weeks apart, as the oil in the torque converter doesn´t come out when you pull the plug.
Does it go into passing gear, when the gas pedal is depressed, close to the floor? If not, or if it downshifts (goes into passing gear), to soon. I can give you some tips on adjustment, this adjustment also affects normal shifts.
Could just be a tired transmission, time soon for some maintenance. My wifes 87 would slip going into second on occasion. Did it for years, without any serious problems. I didn´t tow with it much, and took it weasy in the mountains, to make it last longer.
Many dealers use ATF transmission fluid in the AW4, Dexron seems to work better and is what is recommened in the manual. Dexron has higher friction properties.

 

[Bounty__Hunter]

I reread (slower) and it sounds like an auto. I think MudderChucks solution is your best bet short of tearing the transmission apart.