4L80E & TH400 Tech.

[1972K20]

I'm in the process of getting parts for a 12V Cummins/4L80e/NP205 build. I'm planning on using a 2wd version of the 4L80E because I've read it's easier to adapt a NP205 to the 2wd 4L80E because of the output shaft. The Cummins will be stock, but I want the trans to hold up to towing occasionally. When I have the 4L80E rebuilt, I'd like to do some upgrades. I'd like to do it myself, but I don't think I can. What up-grades would you recommend? Do you know of any reputable shops in Alabama that could do this kind of work? Would you recommend someone that has never rebuilt a transmission to try rebuilding a 4L80E?

[picklito]

I did TH400-to-NP205 years back and it was done with all stock parts. Very slick combo. I bet the 4L80E, being similar, will have a comparable option of parts. Can't help you with the upgrade part, though.

[clinebarger]

Originally Posted by 1972K20

I'm in the process of getting parts for a 12V Cummins/4L80e/NP205 build. I'm planning on using a 2wd version of the 4L80E because I've read it's easier to adapt a NP205 to the 2wd 4L80E because of the output shaft. The Cummins will be stock, but I want the trans to hold up to towing occasionally. When I have the 4L80E rebuilt, I'd like to do some upgrades. I'd like to do it myself, but I don't think I can. What up-grades would you recommend? Do you know of any reputable shops in Alabama that could do this kind of work? Would you recommend someone that has never rebuilt a transmission to try rebuilding a 4L80E?

Don't need much for that build, The MOST Important thing to get is a GOOD Converter! Diesels are extra hard on them!!
Give Circle D Specialties a call....They will hook you up with a nice converter.

Build list....

Dual Feed the Direct Clutches as outlined on page 1

Replace ALL Bushings.

Run High Energy Frictions in the Forwards, Directs, & Intermediates! Borg Warner, Raybestos, & Alto all make High Energy Friction Modules. The Lo-Reverse Band has to be bought separately unless it comes in a kit...

Replace all Steel plates.

Replace the Pump Gears.

Replace all 3 Sprags/Roller Clutches.

Spiralock Intermediate Clutch Snap Ring, http://www.ckperformance.com/View/TH...UTCH-SNAP-RING

Actuator Feed Limit repair kit, http://www.transgo.com/products.php?...dcountview=Yes Does 6 Valve bodies...You guys building 4L80E's need to get together to spread the cost of this kit......

AFL Filter End Plug, http://www.sonnax.com/parts/2031-afl...lug-o-ring-kit

Large Ratio Boost valve, http://www.sonnax.com/parts/2170-lin...re-booster-kit

Line to Lube Pressure Regulator Valve, http://www.sonnax.com/parts/1989-lub...egulator-valve

TCC Regulator Valve, http://www.sonnax.com/parts/2025-tcc...ator-valve-kit

Torlon Check Balls (you need 8), http://www.sonnax.com/parts/1689-checkball

No Walk Case Busing, http://www.sonnax.com/parts/1981-case-bushing Requires careful installation, Cannot use a typical bushing driver...The bushing will break!