WTF is wrong with this damn tranny
Thread Starter
TECH Apprentice
Joined: Apr 2003
Posts: 301
Likes: 0
From: Conway, SC
WTF is wrong with this damn tranny 
OK this is kind of long-winded, but stay with me.
The Rig: 2002 Chevvrolet Silverado 1500 4.8L/4L60E
The Mods: CAI, Predator Programmer, NOS Nitrous, Gibson Headers and Cat-Back, TCI SF3000, TCI Shift Kit, Billet Servo, 4.10 rear gears, Powertrax Locker, 20's.
(Underlined parts were not installed at beginning of scenario.)
I put my truck on the dyno a while back 3 Fridays in a row. 3 pulls each day. After the 2nd Friday, I noticed the tranny starting to slip into 2nd a little bit. It got progessively worse. Then I put my shift kit and 4.10s in. After this, it was horrible and would take several miles to get into 4th. So for a few more weeks I drove it. 2nd was now taking quite a while to come in and 4th was completely gone.
One day on the way to school, I had to slow down (stupid people) and when I started back up, I only had 1st. Changed fluid and filter...still only 1st. Tear apart tranny and find out that the forward clutch pack (first pack on bellhousing side) was absolutely burnt up. Replaced it and 2-4 band. Reassemble with TCI SF3000 converter and TCI Tranny Cooler. Now I only have 2nd and reverse (have had reverse whole time). Put it on the scan tool (GM Tech II) and the solenoids are activating. Thinking maybe I had some sticking valves, I put in a new valvebody. Still only 2nd and reverse.
Please tell me WTF is going on. I have simply run out of ideas and I am very frustrated. I also do not have $1000 to **** away on this thing. Really could use some advice. Thanks!
Last edited by Silvette_02; Oct 18, 2004 at 02:11 PM.
Staging Lane
Joined: Jan 2004
Posts: 54
Likes: 0
From: San Antonio,TX
a shift kit isnt going to fix a slipping condition..if the trans was shifting through all the gears before the shift kit install, you probably did something wrong..im not trying to slam you aor anything..im just speaking from experiance...forward clutches usually burn because of a bad forward piston Seal or its cracked..did you dissassemble the entire input drum??or just replace the clutches..
make sure your getting the right line pressure..put a guage on it
check your voltage at the trans while your cranking..if voltage drops below 9.6v it could caust the trans to go into limp mode..
make sure your getting the right line pressure..put a guage on it
check your voltage at the trans while your cranking..if voltage drops below 9.6v it could caust the trans to go into limp mode..
Thread Starter
TECH Apprentice
Joined: Apr 2003
Posts: 301
Likes: 0
From: Conway, SC
It was acting the same before and after the shift kit install. Slipping but not missing gears. Uh, I'm a little confused as to disassembling the whole input drum. I took it out was kinda messed up from the band, but most of the scratches came out with a little emery cloth. Is there more to the drum than the clutcher? Not meaning to sound stupid, but I'm just unsure of what your saying.
Where do I check voltage?
Thanks
Where do I check voltage?
Thanks
Staging Lane
Joined: Jan 2004
Posts: 54
Likes: 0
From: San Antonio,TX
the drum that the band rides on is the reverse drum..you need to check the rev drum with a straight edge to make sure the band didnt dish the drum..lay the straight edge across the drum..you should not be able to see light underneath it..if the drum is dished the band only has contact on its outer edges and will eventually burn...
the input drum has the forward, coast, and 3/4 clutches..there are three different pistons in the input drum..
you check voltage at the E pin..its pink..it should be the only wire with 12v when the key is on..check it at the trans not the computer..could be fine up top but not at trans
the input drum has the forward, coast, and 3/4 clutches..there are three different pistons in the input drum..
you check voltage at the E pin..its pink..it should be the only wire with 12v when the key is on..check it at the trans not the computer..could be fine up top but not at trans
Last edited by patriot68; Oct 18, 2004 at 11:23 PM.
