4l60e shift problem
Need more details... will it shift if you try it manually? Does it shift under part throttle okay? If it will shift automatically under part throttle while left in D or 3 but not under heavy, wide open throttle conditions, then chances are it's in the tune.
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
By "heavy throttle" do you mean WOT? WOT (typically over 96% throttle, but programmable) uses different shift tables that the partial throttle shift tables. If the WOT shift tables were way wrong, it might not shift.
Edwardzracing: Not to hijack this thread, but if you could explain to give a link to "Shift times", that would be appreciated. I know most other trans tuning tables, but have no idea what "Shift times" does.
Edwardzracing: Not to hijack this thread, but if you could explain to give a link to "Shift times", that would be appreciated. I know most other trans tuning tables, but have no idea what "Shift times" does.
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
This sounds like the part-throttle shift tables are way off. This could be because the PCM doesn't know the speed of the car because the rear-end ratio is tuned incorrectly, the VSS is bad, etc.
Is your speedometer connected to the PCM? Is it accurate?
I would use a scanner (like HP Tuners) to view/log what speed the PCM thinks the car is moving at.
Is your speedometer connected to the PCM? Is it accurate?
I would use a scanner (like HP Tuners) to view/log what speed the PCM thinks the car is moving at.
I have the same problem and i am my tuner. If i set the shift points for wot way low, then it will shift but if i set them to over 6100 rpm then it just blows right by it, hits the limiter hard. I'm very sure its not in the tune. A shift kit seems like a logical solution. I'm really considering a 4l80E for mine but its a heavy truck. I hopes you find a solution and post it up. If it does turn out to be the tune, that will be good news because it will be Ann easy fix.
