Originally Posted By: SteveSRT8
Same here. I guess all those cadillac CTS-V owners (Vettes and Camaro's, too) at the strip with 600-800 hp are running a light duty cycle!
And I can point to the biggest trans repair shop in my area who will badmouth 4L80-E's all day long as weak and poorly designed.
In short you know what you see, we love the 6L90's, they are doing well here in the 3500 vans at 9k pounds every day...
Well, I rebuild 6L80E's in Vette's & Camaro's all the time...Same issues as the 6L90E. They Burn Frictions more often in the performance cars vs the trucks. I've rebuild some with around 20,000 miles on them.
4L80E's are very good units.....Its a electronic TH400 with a Overdrive Clutch pack, Planet, Sprag & Lock-up converter. You can throw a boost valve & a shift kit in a used one & make it hold 600hp.
Throw in a Billet Input Shaft, Aluminum Direct Drum w/ 36 element sprag, Internally dual feed the Directs, High rate direct return springs, HD Intermediate snap ring, Remove the Forward Clutch piston divider & you have a unit capable of 1200 HP. That's using STOCK GM/Borg Warner Frictions.
I have never heard a builder badmouth a 4L80E, Sure they have a few issues the TH400 did not.
TCC lock-up issues causing wrong ratio codes & converter clutch failure.
Forward Drum bushing wear that takes out the forward clutch sealing rings then the forward clutches, But never seen this issue on sub 200,000 mile units. Most in the 300k-400k range.
The Express/Savanna 3500's didn't use 6L90E's 'til 2010/2011, So I'm assuming you have had some 3500 Vans with 4L80E's in the past? Did you have issues with them??
Some clutch pack pictures from a 6L80E out of a 2012 Camaro SS with Cam/Headers at 32,000 miles.