PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

4l80e problem related to conversion harness?

Thread Tools
 
Search this Thread
 
Old Aug 25, 2017 | 02:16 PM
  #1  
Longblue's Avatar
Thread Starter
Staging Lane
 
Joined: Mar 2016
Posts: 51
Likes: 1
Default 4l80e problem related to conversion harness?

I'll ask here and post on my thead in automatic transmissions concerning a 4l80e overheating issue on a friends built truck. Has anyone had an issue with a 4l80e conversion harness causing an overheating issue due to ISS/VSS signal problems?

Found out that my buddy is using a PCM of NC 4l60e to 4l80e conversion harness. Apparently it doesn't use the front ISS signal and then some parameters in the trans have to be tuned out? Was wondering if this might be presenting as some sort of slip issue to the ecm/tcm and causing the excessive heat?

I used the Speartech and it does use the ISS since the 4l60e had it internally.

Thanks
Reply
Old Aug 26, 2017 | 03:11 PM
  #2  
2xLS1's Avatar
TECH Senior Member
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (25)
 
Joined: Nov 2001
Posts: 5,649
Likes: 9
From: Warr Acres, OK
Default

Did you change the 1,2,3 and 4 gear ratios in the calibration to match the actual ratios the 4L80 uses or are they still set to the 4L60 ratios?
Reply
Old Aug 26, 2017 | 04:22 PM
  #3  
Longblue's Avatar
Thread Starter
Staging Lane
 
Joined: Mar 2016
Posts: 51
Likes: 1
Default

I will pass this on. I'm not the tuner but tuner is very competent so hopefully not been overlooked. Thanks for the insight.
Reply




All times are GMT -5. The time now is 02:16 AM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE