The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 99-06 GMT800 Chevy and GMC Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 11-22-2012, 03:01 PM   #1
MJN
Registered User
 
MJN's Avatar
 
Join Date: Feb 2000
Location: Maquoketa, Ia/ Orr, Mn
Posts: 3,093
02 Yukon XL 2500 trans issue??

I've got a '02 GMC Yukon XL 2500 6.0L with 175K miles and lately noticing a strange shifting issue...I think. The engine runs great, no codes or dash lights, uses no fluids and no leaks from anything. The issue shows up after a cold start. If the truck is cold and you go to drive or accelerate up hill or from a stop using mid-throttle or more without letting it run for 5 min or so it feels like the torque converter locks up in second gear or the trans skips 2nd and grabs 3rd instead. If you let off the gas the RPM's come back and then you can drive normally. It goes into all gears good, shifts great and doesn't have this problem after being driven or warmed up and I've never overheated the transmission and given it regular fluid flushes and filter changes. I've read the fuel pressure regulators are common issues, could this be a cause?
__________________
'51 South Bend Model "9A"
'56 Chevy 3600 NAPCO
'74 Chevy Cheyenne Super K20-restored on 37's
'72 GMC Sierra Custom K2500- in progress
'08 GMC Envoy Denali
'12 GMC Sierra 2500HD Denali
'17 GMC Yukon XL
VCCA member #58596
http://www.nohrco.com
MJN is offline   Reply With Quote
Old 11-23-2012, 08:02 PM   #2
clinebarger
Senior Member
 
Join Date: May 2009
Location: Fort Worth, TX
Posts: 6,370
Re: 02 Yukon XL 2500 trans issue??

Thats a weird one.
If shift solenoid "A" was stuck "ON" while cold, It would do a 1-4 shift.
A sticky 1-2 shift valve can do the same thing. (Not common)

I would put shift solenoids "A" & "B" in it, Along with a new EPC force motor.
clinebarger is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 03:57 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.
Copyright 1997-2025 67-72chevytrucks.com