Info: 4l80e/6.5 NA Transmission Limp Mode!! - Diesel Place : Chevrolet and GMC Diesel Truck Forums
 
Home Forum Market Place Garage Tuning Library DTC Tool Register Vendors
Go Back   Diesel Place : Chevrolet and GMC Diesel Truck Forums > GM Diesel Engines > 6.5L Diesel Engine
Register FAQ Forum Rules My Replies My Threads Mark Forums Read Advertise

6.5L Diesel Engine Discuss the 6.5 GM diesel engine & associated components. Automatic transmission questions & problems belong in the 4L80/85 - 4L60E - 6L90 Transmission Forum

DieselPlace.com is the premier Duramax Diesel Forum on the internet. Registered Users do not see the above ads.
Like Tree9Likes

Reply
 
LinkBack Thread Tools
Old 07-02-2018, 04:28 PM   #1 (permalink)
rkfmninja13
Clutch
 
rkfmninja13's Avatar
 
Join Date: Jul 2018
Location: West Texas
Posts: 60
iTrader Score: 0 reviews

4l80e/6.5 NA Transmission Limp Mode!!

Hello all new here to the forum and I'm having an issue with my newly purchased 6.5l Naturally aspirated 4l80e combo in a '95 Air Force box truck. I bought it from a friend not running as the battery's we're removed because of a charging problem, it would drain a battery left not running for 3-5 days. The truck has 42000 miles on it. Before getting it running I replaced 2 pulleys the serpentine belt , fuel filter, oil cooler lines top and bottom, oil and filter and soddered alot of wires that rats had eaten away at pretty badly. Truck fires right up after purging the injectiors and 2 new 600cca batterys ran good and idled pretty rough for 20 minutes I added alot of Lucas and some farm diesel and it cleared up.. come test drive time it seems the trans isn't shifting either out of 1st or out of 2nd I have reverse and 1 forward gear so I come back drop the pan and it's nasty brown pink and like water thin no burnt smell just really old fluid so I replaced filter added 5 qts and tried it after that it shifted great for 2 weeks I go out of town for a week and the truck won't start again and battery's we're reading 6 volts I charged everything up tightened up a not so snug ground on the front battery and it started up now the ses light is on and wouldn't you know it back in damn limp mode.. I drove it to a local auto store and where over the phone they assure me that they have an obd1 reader so I lug it a few miles to the parts store trans hit 230 on the gauge(mechanical autolite) measured at the outlet of the trans pump. They couldn't read my vehicle on their reader so fusterated I drove it back home trans at 210 for 5-7 minutes and shut it down...next I tried the paperclip meathod by jumping terminals a and b on my 12 pin port and nothing happens no 12 code no nothing the ses light just remains on so in vein I pulled the pan off the transmission again replaced filter and changed solenoids a and b as well as the vss input sensor on the side of the case slap it back together and nothing still in limp mode...I checked the plug and I have one pin hole of the plug that reads 12.4 volts so the transmission has one hot location on the plug is this correct or shouldn't a few other holes show hot? I've checked the wire for breaks and chaffing and everything in between. What can I do to get this thing out of limp mode?(an assumption) it's also worth noting that even though the truck won't up shift no matter what gear I have it in if I pull it from drive into second it kicks down like it was in gear but it's like that gear doesn't exist and it will only kick down if it's very part throttle if I'm accelerating and shift it manually up or down it does nothing reverse works flawless and engine is very responsive and alot of torque but it's just not upshifting. How can I read the codes or at least reset the 4l80e to get it out of limp mode? I've taken the negative terminals off and let it sit for 10 minutes to 1 hr and each time the ses light returns and it's still limping. Any help or advice is greatly appreciated.

__________________
1995 Air Force box truck 6.5L N/A
Offline  
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 07-02-2018, 04:43 PM   #2 (permalink)
rkfmninja13
Clutch
 
rkfmninja13's Avatar
 
Join Date: Jul 2018
Location: West Texas
Posts: 60
iTrader Score: 0 reviews

One local shop said they have a quality obd1 reader but if they can't read it it'll still cost 80$ which is sort of crazy to me but they're almost the only person in town that will even look at it. I'd love some advice on how to get the obd1 port working if it's at all possible but I've heard that '95 commercial/government trucks were bastards as far as the obds and ecus. this is my first Diesel as well as my first auto trans that's electronicly controlled. Should I just see if that shop can read it with a better reader or is it possibly not going to read no matter what? Thanks again!

__________________
1995 Air Force box truck 6.5L N/A
Offline   Reply With Quote Quick reply to this message
Old 07-03-2018, 03:49 AM   #3 (permalink)
davester
Diesel Prodigy
 
Join Date: May 2015
Posts: 4,073
iTrader Score: 0 reviews

1. paragraphs are your friend. one big block of text sucks to read and a lot of people don't bother.


2. 5 qts is likely too little atf for the transmission. Not good for the transmission and can cause high trans temp as well. And it may or may not shift right.
__________________
2004 GMC Sierra 3500 C&C, added 4WD, 6.0L gas, Extended Cab, SLE, Transgo 4L80e-HD2 kit installed
Whee! Dually Club Member #1109
Offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 07-03-2018, 06:19 AM   #4 (permalink)
Tomcats
Diesel Head
 
Join Date: May 2009
Posts: 698
iTrader Score: 0 reviews

What he said ^^ about paragraphs, very hard to read with no white space...



Most people here use GMTDtech There is a free version but do not think it reads transmission, or at least not all of it... Paid does...



You will need an ALDL cable or adapter.



Engh Motors - Makers of GMTDScan, the PC OBDI/ALDL scan tools for 1994-1995 GM 6.5TD trucks.
__________________
94 C3500 Turbo Diesel Dually Crew Cab long bed. 3-inch down pipe 3-inch exhaust no cat no muffler, Snorkel open, boost gauge, fuel pressure gauge Re-manufactured F-series Jasper engine 50,000 miles, now nearing 100,000 miles Zero.001% blow by PMD 4 years IP DB4 S5068, last replaced under warranty 100 years ago.
Leroy Lift Pump wiring harness.
4.10 gears

Member #1149 of the 3500 Dually Club!


Latest Project No Past History.
97 C3500 6.5 Turbo F series Straight Pipe No Cat 300,000 Miles looks to be rebuilt. Still sitting where I parked it a few years back. Finally started removing things in search of an injector or head problem.
Offline   Reply With Quote Quick reply to this message
Old 07-03-2018, 10:47 AM   #5 (permalink)
rkfmninja13
Clutch
 
rkfmninja13's Avatar
 
Join Date: Jul 2018
Location: West Texas
Posts: 60
iTrader Score: 0 reviews

Sorry about the lack of paragraphs I'll keep that in mind in the future. The trans fluid is reading perfectly on the stick at 175 degrees in park and this was happening before I ever drained and replaced any fluid...and after doing some research it looks like I may not have a ecu at all just a tcm on this vehicle I'll post back with pics soon
__________________
1995 Air Force box truck 6.5L N/A
Offline   Reply With Quote Quick reply to this message
Old 07-03-2018, 10:53 AM   #6 (permalink)
OkDually
Administrator
 
OkDually's Avatar
 
Join Date: Jul 2013
Location: N.E. Oklahoma
Posts: 13,418
iTrader Score: 0 reviews

DieselPlace.com Lifetime Premium Member

Be sure to study the FAQ page in the 4L80 trans section:
https://www.dieselplace.com/forum/57...-transmission/

__________________
1996 K3500 6.5L,( "F" Eng #141 cast block) 5 speed manual, crewcab, dually longbed: 208,000mi.
Diamond Eye 4" Turbo Back Exhaust w/2.5" Flo-Pro Crossover
AirDog II DF165 w/ tank sock delete - XDP
TD-Max boost controller - Kennedy Diesel
OPS extension hose - Leroy Diesel
Glow Plug Harness- PT Wiring Solutions
Glowshift Maxtow EGT,Boost, Fuel gauges
Boost & Fuel Pressure Bolts - Leroy Diesel
2/0 Battery Cable Upgrade - PT Wiring Solutions
PMD w/#9 resistor and Re-Location Kit, mounted to bumper - Leroy Diesel
GM-5 Turbocharger
4.10 gear ratio
OptiLube summer + Formula


Proud member #1039 of The 3500 Dually Club

Offline   Reply With Quote Quick reply to this message
Old 07-03-2018, 12:48 PM   #7 (permalink)
Glagulator
Diesel Superstar
 
Join Date: May 2005
Location: Very south TEXAS, Formerly Wisconsin
Posts: 3,620
iTrader Score: 5 reviews

If you have a mechanical IP then you have a TCM.
Is your rig a truck or a van?
__________________
There are 10 kinds of people in this world; Those who understand binary and those who don't.

99 CREW LONG SRW C3500 work truck 199k+ mi. orig. motor & trans 4.10, modded engine harness, new oil cooler & lines, all new front end parts and poly bushings, trans poly mount, all new brakes.
96 SUBURBAN K2500 wife's truck 210k+ mi. orig. motor & trans, 3.73...
95 C2500 Suburban 6.5td HO w/p, timing set, HB & pulley, all rubber hoses, modded engine & main harness, converted to OBD2, PMD to bumper...
95 C1500 Suburban 6.5td rebuild tranny, convert to DB2, replacing as many parts as I can.
96 C2500 Suburban 7.4L converting to 6.5td w/ DB2, 4L80, 3.73
Offline   Reply With Quote Quick reply to this message
Old 07-03-2018, 01:51 PM   #8 (permalink)
rkfmninja13
Clutch
 
rkfmninja13's Avatar
 
Join Date: Jul 2018
Location: West Texas
Posts: 60
iTrader Score: 0 reviews

Pics
__________________
1995 Air Force box truck 6.5L N/A
Offline   Reply With Quote Quick reply to this message
Old 07-03-2018, 01:56 PM   #9 (permalink)
rkfmninja13
Clutch
 
rkfmninja13's Avatar
 
Join Date: Jul 2018
Location: West Texas
Posts: 60
iTrader Score: 0 reviews

This is all I could find as far as electronics, I have a ecm fuse but I believe this is a tcm?
Attached Images
File Type: jpg IMG_20180703_114610_1530640344913.jpg (46.5 KB, 4 views)
File Type: jpg IMG_20180703_114621_1530640492633.jpg (49.7 KB, 4 views)
__________________
1995 Air Force box truck 6.5L N/A
Offline   Reply With Quote Quick reply to this message
Old 07-03-2018, 02:55 PM   #10 (permalink)
Glagulator
Diesel Superstar
 
Join Date: May 2005
Location: Very south TEXAS, Formerly Wisconsin
Posts: 3,620
iTrader Score: 5 reviews

TCM for sure.
Try reading the codes by shorting DLC "B" to battery ground instead of DLC "A" and see if codes flash.
You might pull the connectors on the TCM and see if the terminals are clean on both the TCM and the connectors.

__________________
There are 10 kinds of people in this world; Those who understand binary and those who don't.

99 CREW LONG SRW C3500 work truck 199k+ mi. orig. motor & trans 4.10, modded engine harness, new oil cooler & lines, all new front end parts and poly bushings, trans poly mount, all new brakes.
96 SUBURBAN K2500 wife's truck 210k+ mi. orig. motor & trans, 3.73...
95 C2500 Suburban 6.5td HO w/p, timing set, HB & pulley, all rubber hoses, modded engine & main harness, converted to OBD2, PMD to bumper...
95 C1500 Suburban 6.5td rebuild tranny, convert to DB2, replacing as many parts as I can.
96 C2500 Suburban 7.4L converting to 6.5td w/ DB2, 4L80, 3.73
Offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Diesel Place : Chevrolet and GMC Diesel Truck Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

PLEASE READ! You must check your email inbox for the confirmation link to complete registration. Please check your spam box if you do not see the email in your inbox.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Insurance
Please select your insurance company (Optional)

Log-in


Thread Tools

Posting Rules
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Transmission Limp Mode Djreversal Allison Aftermarket 1 01-14-2018 11:17 AM
LMM: Dealer can't isolate problems, P0706, P0708 DouglasD Duramax Fourth Generation: 2007.5-2010 (LMM) 10 11-27-2017 06:07 AM
Filter numbers? freewayrandy Allison OEM 1 05-20-2016 11:46 AM
"ECM 1" Fuse Keeps Blowing, Transmission in Limp Mode. jamesg123 6.5L Diesel Engine 27 02-01-2016 09:23 AM


All times are GMT -4. The time now is 05:22 AM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Shoutbox provided by vBShout v6.2.1 (Lite) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd. Runs best on HiVelocity Hosting.
© AutoGuide