djoker04

Hey guys, found your site looking for info and since I'm use to being on Sportbike style forums, I'm glad I found this! So hopefully I can get some help. Bought a 99 Astro with 113k on motor 152k on body. Knew it had a tranny problem but for what i paid for it, I'm not going to complain. Here's the issue....switched from 1st to 2nd but from 25mph to 30mph the motor just races until i let off the gas then it will switch. Now I did some esearch and found this site http://www.drivetrain.com/parts_cata...erInstallation
and 1/2 way down you have the troubleshoot section that shows my exact issue. (Middle case leak in the 2nd gear apply circuit (servo assembly or 1-2 accumulator). Doublecheck by using the pressure gauge and watch for a big drop when the PCM commands 2nd gear. Worst case poor line pressure rise (see below).Now with this symptom I'm thinking because of the leak I'm losing pressure because I also have a leak poss coming from the oil cooler lines.It also says to look into changing my Throttle Position Sensor. I just did a new filter and oil change with one bottle of Lucas Tranny oil. . I bought a Ultra Oil Cooler and will get it today! Installing this weekend. Any other suggestions.I read somewhere that i might need to tighten up Tranny Valve Body to it's proper torque. PLEASE DO NOT SUGGEST AAMCO...I just read waaayyyy to many bad reviews on them. Thanks for any help. Once I get her running correctly I'll be modifing it so stay tuned for pics!!

djoker04

Sorry Bro not the one! What does that mean?

roc0999

welcome to the site, I'm not sure about your tranny problems but someone here should be abel to help , good luck

djoker04

Thanks. I bought a GM Service and Repair Database software and it came in yesterday! After research again, I read that the Valve Body could have things clogged in it in certain areas. So a possible flush might work.(1 of the recommendations) (Gotta go buy a Printer) But my check engine light is not on! But i'm going with the 1st step and change the oil cooler. if that does not fix it then I'm going buy a rebuilt/used Valve Body. If used get it checked out! I have a strong feeling this will not be costly fix!

ihatemybike

Does the trans eventually get into third or is it dropping back into second? These transmissions are known to have the 3-4 clutch pack wear out due to the stock smooth feeling soft shift. I just had Green's trans rebuilt because of this. A worn out clutch will not set any engine codes, where the other things you mentioned should. When you dropped the pan was there any fine gritty stuff in the bottom of it?

djoker04

No! it will go to 3rd once i pass 35+. I have the new Tranny Oil Cooler and just ordered New Oil cooler lines. According to the Data Base DVD i have I will also replace the TPS. The pan was actually clean nothing on the magnet! I will take it to my garage today to have him clean the engine and get her ready for the work...I'll keep you guys posted!!

Thumper_ehhhhh

Trannys are outta my league. I will however tell you what I did with mine. We have a very good tranny shop in town. I took it to them. They fixed all my problems. To me though. I would start with a filter and fluid change. It could be as simple as that. I ended up having the wrong filter in mine. It worked 100% after that.