Something to add to the ever breaking 4L60E

[Dwayne]

I would say on the performance side. The 4L80E is a truck automatic transmission that was introduced by GM in the early ’90s. It basically uses many of the same internal components as the TH400 but has an overdrive Fourth gear and uses electronics to control shift points, firmness The reason you haven’t seen many of them in hot rods is because the electronics run off the vehicle computer —which most older cars don’t have— and there hasn’t been an easily programmable, stand-alone computer available to make it work in a carbureted application which has changed over the years to make it work. The question remains is Why on earth would GM put such an anemic transmission in a heavy ½ ton truck, Avalanche, or Escalade? These transmissions barely hold up to the punishment a stock LSX based engine generates. Now add a few modifications to it, trust me, it won’t last long. It’s great the new generation GM trucks with LSX engine variants are probably the most reliable and powerful engines out, but it would be nice if these transmissions would last a little longer. Fortunately, GM does produce a beefier transmission that can handle any type of modification you install onto your truck and all the punishment you can throw at it. They are only available in the HD ¾ trucks with 6.0L and 8.1L engines. In stock form, I’ve seen these transmissions handle over 600-fwhp for several years. Add a few performance parts to them, and you have a transmission that will handle more than the engine can with full performance modifications. GM’s tough transmission with an overdrive is the 4L80e. Also The 80e trans is longer than the 60e transmission so the stock cross member has to be modified. Parts needed to complete the 4L60E to 4L80E transmission swap:


FLT fully built 4L80E – Finish Line Transmissions
4L80e torque converter – Yank Converters
Dealer OEM items:
80e flex plate – PN:12551367
Flex plate bolts – 12563533
Flex plate spacer – PN:12563532
Torque converter bolts – local parts store
Lower bell housing – PN:15765723
Lower bell housing bolts – PN:11516328
80e gear selector cable bracket – PN:
HD truck dipstick tube – PN:15832205
Transmission mount – reuse PN:22201140
2002 ¾ ton HD Suburban driveshaft – PN:15771996
1350 series rear end yoke – local gear shop
Pre ’99 rear end seal – NAPA PN:19273
PCM 80e calibration – Nelson Performance
60e to 80e conversion harness – Nelson Performance
Case of Dextron III transmission fluid – NAPA - Pennzoil

Tools used during swap:

Complete metric socket and wrench set
Various lengths extensions
Cutting wheel or chop saw
Mig welder


Fabrication required:

Cutting and welding the crossmember.


Suppliers:

Finish Line Transmissions
801 N. Central
Wood Dale, IL 6091
Ph: 630-350-7776
[email protected]
www.finishlinetrans.com


Nelson Performance
10034 Roosevelt Av.
San Antonio, TX 78214
Ph: 210-626-0278
www.nelsonperformance.com


Yank Performance Manufacturing
Ph: 775-826-9955
www.converter.cc

Lastly better have some Money for this ...