Bad tranny?

[Twiz]

1990 Silverado k 2500 with auto trans.

Drove my truck yesterday and she drove great. Fired her up this morning to get to work and let her warm up for about 30 mins. When I jumped in and shifted into reverse she rolled forward about 2 inches. Neutral is now drive. Drive is drive and shifting back into park makes her roll forward another 2 inches. Didn't have time to look for anything yet but hoping you guys can give me a heads up. I've googled it but not finding anything that relates to my problem. The only thing I've found is if reverse gos out the whole tranny is bad. I really hope not.

Thanks in advance.

[HondaMartin]

Originally Posted by Twiz

1990 Silverado k 2500 with auto trans.

Drove my truck yesterday and she drove great. Fired her up this morning to get to work and let her warm up for about 30 mins. When I jumped in and shifted into reverse she rolled forward about 2 inches. Neutral is now drive. Drive is drive and shifting back into park makes her roll forward another 2 inches. Didn't have time to look for anything yet but hoping you guys can give me a heads up. I've googled it but not finding anything that relates to my problem. The only thing I've found is if reverse gos out the whole tranny is bad. I really hope not.

Thanks in advance.

Mine roll forward a little bit before it locks in park. But i'm thinking its just the shifter linkage. Its more that likely the linkage on the tranny. But it could be in your steering collum as well. Hopefully someone with the experience will chime in.

[Twiz]

I forgot to mention that yesterday the throttle cable stuck and I drove it anyway until it got warm enough to release. Don't know if it trying to downshift running high rpms would do anything.

[Twiz]

Just did some checks, the linkage is mechanical, not a cable. The fluid cold not running is way overfull. Last I checked it is was right in the middle. Never found any leaks. Although if it was leaking it would be low, not high. I've got it warming up right now to see if the lvl will drop to normal. I'll get back on after I do a few more checks.

Oh yea, once it started it rolled forward about 2 inches.

[Twiz]

Tranny is way over serviced! No idea where the extra fluid came from. Anyone ever hear of the transfer case seal going out and filling the tranny? It also smells burnt as hell. I'm gonna check the transfer case tomarow morning and suck some fluid out of the trans and see if that changes anything before I spend money. Let me know if you guys think of anything.

[93bowtie]

I would begin preparing to spend 1500 on a transmission rebuild man... That is how mine started... From beginning to end

[95 S_Trucker]

The fluid will always be high when not running. It needs to be checked when it is running.

The fact that your truck does not move in reverse and the fluid is burnt means its time for a new one or a rebuild.

[93bowtie]

Mine just came in the other day from the shop..

[93bowtie]

Another pic

[Twiz]

Originally Posted by 95 S_Trucker

The fluid will always be high when not running. It needs to be checked when it is running.

When I checked it it was way too high for not running.

After syphening some fluid out of it I got it where it's supposed to be, and test drove it. No change. Called a reputable transmission shop in town and they said it was the front clutch. Lucky me I alredy have a spare tranny for it, just been sitting for a while, not sure if it's gonna work. But that's my update.

[95 S_Trucker]

It will be way too high not running. There aren't any marks on the dipstick for not running. It will be inches higher than the hot/cold sections.

[Twiz]

So, since I'm pulling this tranny, I figured I would replace my u-joints while I'm at it. No idea when they were last done. Looking at some reviews though has me wondering. What brands do you guys use? And are they all the same around the truck? I've only ever done u-joints on my 68 c10 and those were the same. Never worked on a 4x4. I assume they would be the same but assuming usually ends in me making as ass of myself.

[Twiz]

Got the drive shafts out tonight. Tomorrow will be unbolting the transfer case from the tranny. Everything except the cross member. Then wednesday will be dropping it, and if I have enough time unbolting the tranny. I'll keep you guys updated.

[iluvmy72]

Originally Posted by 93bowtie

Another pic

I was told these cases are getting hard to find. Many are breaking

[special-K]

just to be perfectly clear, because I don't see you acknowledge it, the transmission level gets checked with engine running and a reading with it not running means absolutely nothing. An automatic transmission is basically a hydraulic pump with internal valving. I don't know what trans you have, but a 4L80E will lose reverse due to a bad sensor. and yes, a seal can go bad and allow fluid transfer between trans and transfer case

[Angryman117]

I have the same thing happen to me. I had no reverse, neutral, and when in park the engine idled really low due to having a load. Turned out the forward clutches were fused togeter.

[Twiz]

Ok, just so everyone is clear, I know I should check the fluid running, warm and in nutrual. I was trying to see if anyone else knows about the issue I was having. I thought I made it clear I knew how to check the fluid properly but I guess not. I also know that when it is cold like that it will look over serviced. I was trying to say that it was far more over serviced than just cold not running.

And it's been a while since I updated you guys on my progress. Transfer case and tranny is out. Compared the old to the spare. Everything looks good, but no shop in town has a torque converter, so I'm waiting till Monday and I'm gonna call a tranny shop to see if they have any.

And also it's a 700r4.