03silveradoLS

ok little history before the issue...

Drove out to friends house and hour away with plans to pull a trailer with a small horse on it back to his house for him. Before loading up the trailer we decided to drive around the property to check on the donkey he already had out there. Got a little stuck on some mud and put in 4wd to get out, no big deal left it in 4wd while getting the trailer loaded and pulled to the front then put back in 2wd. Pulled the trailer about an hour away to get the horse then an hour back, unload the horse and drop the trailer, during all the everything seemed fine. Truck shifted fine. After a while we left to get something to eat in town, after a few miles down the highway the rpms go up about 3-400 rpm but no change in the speed, felt like maybe it was slipping. Get off the highway and stop, when i take off easy it slams into the next gear, no clunk or anything just really firm shift on all gears. if the the truck sits for a little while then it shifts fine again until it warms back up. Watched the temp gauge and it never went above 180 with or without the trailer/horse. Is it time for a rebuild or maybe just something easier i hope?

truck is a 06 gmc 2500hd with 6.0L 4l80e 4x4, stock except for muffler and 33in tires.

03silveradoLS

ok just brought it to auto zone and had them read read the CEL code.

p0894, read some stuff and it says anything from dirty oil to rebuild entire transmission.

oil look ok but prolly wouldnt hurt to change it and the filter. other than that i really dont want to start throwing parts at it becuase i dont have a money tree in my yard lol. So does anyone have any tricks i can try or if anyone is close to sweetwater/abilene area in texas than can help with efi live to see if we can narrow it down?

also my girlfriend has been driving the truck over the past week since she works pretty close and doesnt have to get on the highway to get there and the truck runs fine except the CEL is on.

1FastBrick

iTrader: (17)

According to what I found the codes are related to excessive TCC slip. They recomend to check the TC Regulator for wear, stator bushings and the TC it self.

You could try Fluid and filter first Since they are regular maintenance items, but most likely It will be something internal.

for example, This guy had an exposed wire.

https://www.performancetrucks.net/fo.../p0894-482030/

I have read else were about a burned up 4th clutch and others have had bad speed sensors.

You might want to Find a competent Mechanic that can test these things and has the right tools to diagnose the issue.

03silveradoLS

yea i read all those posts. tried to see about getting the flush done today but the dealer only does engine oil changes on saturdays, pep boys wont touch it to do the flush since it has a problem. everyone else is closed til monday. got refered to a transmission place by 3 different people so just going to see if he can take a look at it on monday after work. this is the first automatic trans i've ever had **** on me so hoping this guy will let me know so i can learn something lol

03regcab sierra

iTrader: (7)

Let us know wat the problem is. Mines doin the same thing and i cant figure it out

03silveradoLS

finally got my truck into the shop today.

he put a scanner on it and took it for a short drive and it shows 3rd slipping pretty bad and 4th slipping some. guess i gotta start saving for a new transmission

1FastBrick

iTrader: (17)

Bummer... Thanks for updating us though. It may help some one like your self in the future with a similar issue.

03silveradoLS

just an update, yea i know its been a while.

been a rough year, got laid off from my job and was unemployed for almost 6 months so didnt have the money to get the truck fixed so its been babied for a while, no highway and only short distances in town. Since the weather is getting hot again the transmission is acting up more than ever, risked it to meet the guy that bought my jeep to meet him an hour away and on the the way home the trans hit 300* and wouldnt shift past 2nd gear, after i let it cool down it was back to the normal slipping 3rd and 4th but now it gets up past 250 just driving across town, i live in a small town and it only takes me 7 minutes to get from my house to work lol. So i ordered a new trans from a local shop, he gets them from Jasper with a 3 year warranty on them if his shop does the install so hopefull by thursday my truck will be fixed and i can start fixing it up( need alot of cosmetic stuff and a few mods to make it run a little stronger)

bobfig

i hope that jasper lasts. good to hear your getting back on your feet.

03silveradoLS

got the truck back and all is good now. trans came with a 3 year/100k mile warranty so it seems like they stand behind their work. the shop i used i would definately go back too, very friendly folks and quick turn around. i did have a small issue when i tried going down the highway but he told me to bring it back and he would check it out and fix it right away. turned out it was just a clog in the cooler and he reflushed it a few times to make sure it was all cleaned out. he even offered to give me gas money since i was already 45 minutes away and had to come back. his wife/receptionist gave me a hat( i never turn down a free hat lol ) and a coupon for a free car wash.

as far as Jasper i've never heard any bad things about their transmissions or motors, friend of mine's company uses them for all the fleet trucks so they get put through some pretty good abuse. yea its pretty much just a factory build transmission but that's fine for me as i dont plan on going nuts with this truck, just want it to pull my other projects and daily driver.