2002 4l30e shift problem

Discuss anything related to drivetrain problems here (Engine, Transmission, etc)

Moderator: Staff

2002 4l30e shift problem

Postby Rodeo mike2002 » Thu Jun 17, 2021 1:05 pm

I have an 2002 rodeo and the automatic trans went out. Picked up what appears to be a rebuilt trans from a salvage. Installed it shifted fine when it’s cold. However when it warms up it Kinda weird but I can go from first to second ok and then from second it's fine up to like 2200-2500 rpm then it will rev up before it shifts to third. It’s like it wants to down shift before going to third. Let off the gas it shifts and works fine till I stop. No engine or trans lights. Any help is much appreciated
Rodeo mike2002
Drives on Pavement
 
Posts: 5
Joined: Thu Jun 17, 2021 12:33 pm
Has thanked: 0 time
Have thanks: 0 time

Sponsor
 

Re: 2002 4l30e shift problem

Postby Buster28 » Fri Jun 18, 2021 10:10 am

Does the transmission always shift properly when cold?
How long does it take before it starts to have the shift problem?
Was there ATF in the transmission when you bought it?
Did you add or change the ATF?
2002 Rodeo Sport 4X4 3.2L V6
2020 Jeep Wrangler 2dr 4x4 3.6L V6
User avatar
Buster28
4L30E Guru
 
Posts: 11594
Joined: Fri Dec 18, 2009 12:28 pm
Location: RI
Has thanked: 10 times
Have thanks: 1323 times

Re: 2002 4l30e shift problem

Postby Rodeo mike2002 » Fri Jun 18, 2021 6:08 pm

When it’s cold it does shift correctly. But after driving about 15 to 20 min in town it messes up. It had good red atf in it when I got it. Drained it and filed it up after I installed it.
Rodeo mike2002
Drives on Pavement
 
Posts: 5
Joined: Thu Jun 17, 2021 12:33 pm
Has thanked: 0 time
Have thanks: 0 time

Re: 2002 4l30e shift problem

Postby Buster28 » Sat Jun 19, 2021 1:09 pm

Does the problem still occur when the hot if you lightly apply the throttle and slowly accelerate through the gears?
2002 Rodeo Sport 4X4 3.2L V6
2020 Jeep Wrangler 2dr 4x4 3.6L V6
User avatar
Buster28
4L30E Guru
 
Posts: 11594
Joined: Fri Dec 18, 2009 12:28 pm
Location: RI
Has thanked: 10 times
Have thanks: 1323 times

Re: 2002 4l30e shift problem

Postby Rodeo mike2002 » Sat Jun 19, 2021 3:12 pm

Okay so today I changed the fluid / filter and adjusted bands and added Lucas trans conditioner. Drove it. Basically after it gets to operating temp it hesitates going out of second. The rpm will go up but if you let off it will shift. This only is happening once out of every three to four times it shifts. So not every time. When it does shift correctly it shifts smooth. The best I can describe it is it is hesitating before shifting into third gear. Rpm continues up but if you let off it shifts.
Rodeo mike2002
Drives on Pavement
 
Posts: 5
Joined: Thu Jun 17, 2021 12:33 pm
Has thanked: 0 time
Have thanks: 0 time

Re: 2002 4l30e shift problem

Postby Buster28 » Sat Jun 19, 2021 4:38 pm

If the transmission always shifts properly when cold it appears something is sticking when the ATF gets hot. The only thing I can suggest is to replace the brake band solenoid.

To shift from 2nd to 3rd gear the B shift valve is moved to the 3rd and 4th gear position when the Shift B solenoid is de-energized. When the B shift valve is in the correct position pressurized hydraulic fluid is ported through the shift valve as "servo release fluid". This fluid is directed to the piston of the 3rd clutch causing the 3rd clutch to engage, it is also directed to the reverse side of the brake band servo piston causing the brake band to release.

The brake band solenoid is a Pulse Width Modulated (PWM) solenoid as opposed to an On/Off type. Above 13 mph the PCM de-energizes the brake band solenoid (0% PWM duty cycle) causing the brake band solenoid fluid port to be wide open. The wide open port allows servo apply fluid to quickly exhaust through the fluid port allowing the brake band to quickly release. If the solenoid sticks in the closed position release of brake band is slowed down and possibly cause the problem you describe.
2002 Rodeo Sport 4X4 3.2L V6
2020 Jeep Wrangler 2dr 4x4 3.6L V6
User avatar
Buster28
4L30E Guru
 
Posts: 11594
Joined: Fri Dec 18, 2009 12:28 pm
Location: RI
Has thanked: 10 times
Have thanks: 1323 times

Re: 2002 4l30e shift problem

Postby Rodeo mike2002 » Sat Jun 19, 2021 5:46 pm

Thank you. I’ll try that. Very much LT appreciated. I’ll post when I get it changed out.
Rodeo mike2002
Drives on Pavement
 
Posts: 5
Joined: Thu Jun 17, 2021 12:33 pm
Has thanked: 0 time
Have thanks: 0 time

Re: 2002 4l30e shift problem

Postby Rodeo mike2002 » Sat Jun 19, 2021 6:01 pm

Can anyone suggest a brand name and part number for the brake band solenoid for my 2002 4l30e ??? I can’t figure out which one it is??? Thank you.
Rodeo mike2002
Drives on Pavement
 
Posts: 5
Joined: Thu Jun 17, 2021 12:33 pm
Has thanked: 0 time
Have thanks: 0 time

Re: 2002 4l30e shift problem

Postby Buster28 » Sun Jun 20, 2021 7:05 am

The Isuzu/Honda/Acura/ part # for the PWM brake band ("low band") solenoid is 8-96042-632-0. It replaces 8-96041-033-0, 8-96042-006-0, 8-96014-795-0. The same part is also used in Cadillac and BMW 4L30e transmissions. The current OE solenoid is very expensive, you can find older part number solenoids on eBay for much less. Since your transmission having a defective solenoid is just a possibility an inexpensive superseded version is probably the best choice.
2002 Rodeo Sport 4X4 3.2L V6
2020 Jeep Wrangler 2dr 4x4 3.6L V6
User avatar
Buster28
4L30E Guru
 
Posts: 11594
Joined: Fri Dec 18, 2009 12:28 pm
Location: RI
Has thanked: 10 times
Have thanks: 1323 times


Who is online

Users browsing this forum: No registered users and 11 guests