hello, i have searched on here and havent really seen anybody with the exact same problem as me so here gos. i have a 96 blazer LT 4dr 4x4 4.3L. recently, when driving right out of my house the trans does fine shifting through all the gears because i only go up to 35 the posted speed limit.... but once i decide to take a longer trip as in 16 miles, the speed limit goes up to 55. the first half of the trip the car decides to go into over drive and the rpms will be at about 1500 at 45 -50. but once i get up into the higher speeds the transmission will try to down shift and be at about 2300 at 50-55. and the SES light will kick on. once i leave the car sit for a while like overnight and i restart it the light will be off and will not kick on unless i go those speeds again. i have no idea what is happening but it is draining my wallet seeing as i am only getting 12 miles to the gallon. i was thinking about changing the trans fluid once it gets warmer out and seeing if that has anything to do with it.

also i noticed that if i have to put my car in reverse to move the car after starting up it seems like the trans catches and lets go, catches and lets go but after i put it in drive and it warms up it doesnt do this anymore. idk if this has to do with my problem at all but hopefully somebody will let me know. thanks.

 

No responses.... Did you happen to figure out what the issue was? I'm having the exact same problem..... My OD engages fine in the morning when it's cooler out, but in the afternoon when the temp is 90 f, it slips out of OD.. R has been doing the same also... It engages and slips out, kind of grabs when I hit the gas, but slips really bad... Occasionally, R won't even engage

 

i found out that it was a bad input shaft seal on my transfer case. i had to drop the transfer case and switch out the seal. i changed all my fluids while i was at it.

a good way to tell if this is your problem is go to your transfer case, if you have a 4x4. and take out the filler bolt. if trans fluid starts gushing out, you have the bad input shaft seal. it drains your trans fluid out of the trans and sucks it into your transfer case, eventually sucking it into your vacuum lines creating a mess. (what happened to me...) get it checked out as soon as possible.

 

Hi, I have a 1993 Blazer that does almost the same thing. I do not have the problems with the reverse. Mine is overdrive and first gear sometimes. I was just about to pull the transmission out and get rid of it. I will check that first. Might save me alot of work. Thanks.