I have a 1998 tnx jimmy 4.3. 4wd and when you are just cruise at any speed between 45 and 55 it recent up about 200 to 300 rpm...what could it be?

 

first thing i would do is clean the mass air flow sensor.
(square silver looking thing on the air filter hose going to the throttle body).

Take it off,and pick up a can of mass air flow cleaner. Use this ONLY! Spray the inside of the sensor really good and let it dry. reassemble and drive it.

 

Well I gave it nasty today and it hasn't done it since but thanks for the tip....I also was told it could be tcc and it has overdrive

 

I just don't want to put a lot of money in it of I don't need to and it doesn't do it all time...mean if I stop and go up to tht speed it might not do it

 

If its the trans,then you'll be looking at a rebuild later on. Ignoring things is what causes bigger problems.

 

Thanks I just don't want to spend 1200 for a trans and it still does it and its really $20 fix

 

Now,like on mine it goes into overdrive around 52 mph. Once it drops below that you can feel it shift,which is normal. If im cruising around 52 it'll lock in and out of gear until you get away from it.

Id check fluid level after driving it for a while. Make sure its leveled,and you leave it running in park when you check it. If fluid is red,and doesnt smell burnt then just drive it. If its brown,or dirty looking,do a pan service. Not a flush.

 

i had the fluid changed Dec. 6 and it still does it....between 38 mph or 57mph and u can set it at any of the speed in between and it will do it if your under it or over tht speed it fine...no codes but the abs light is on and the driver hub is bad