4L80E

The 4L80E is what we believe to be GM’s best 4 speed automatic transmission to date. Production began in 1991 year models and continued as the 4L85E until the 2009+ model year. Derived from the TH400 which made it’s in the beginning of the “golden era” of muscle cars, the 4L80E is the option of choice for high horsepower enthusiasts whos key focus is making big power reliably, while retaining a near stock feel and Overdrive. The majority of street oriented cars and trucks making over 600 horsepower who want to keep the vehicle as streetable as possible should heavily consider a 4L80E.

We here at North Texas Converter do not believe “one size fits all”, and we prefer anyone who is seriously looking into a 4L80E as an option for their vehicle to give us a call and let us discuss the combination with you to better assist you in choosing the ideal combination for your ride. For simplicity’s sake we have several “starter” 4L80E options to choose from. From there, we can decide whether that will be more than sufficient for your combination, or perhaps there may be something further we can do to give you the best product possible. We refuse to cut corners on the builds, and we will never oversell you on something you do not need, but at the same time we are committed to making sure you are given the best possible combination for your vehicle.

Base build options

All 4L80E’s built by us regardless of build level, come with the following options, making even our “entry” level 4L80E extremely stout and rated for up to 750hp (Nitrous combos excluded)

  • Full rebuild kit
  • Hi Energy clutches
  • New intermediate/reverse bands
  • New seals
  • New gaskets
  • New filters
  • New bushings throughout
  • New thrust washers
  • New low roller/OD roller sprags
  • New OEM Borg Warner 34 element sprag
  • New OEM wiring harness
  • New A/C Delco shift solenoids
  • New OEM pressure manifold switch
  • New HD intermediate snap ring
  • New Sonnax boost valve w/ spring
  • Rollerized internals
  • 6 count frictions for direct clutches
  • Fully splined output shaft for maximum yoke engagement
  • Dual fed 3rd gear clutches
  • NTC hydraulic modifications throughout

Level I 4L80E – Starting at $3,000

Despite being the base model, make no mistake this thing is STRONG and will outperform ANY 4L60E on the market. Our starter level 4L80E comes with all of the items listed above, dyno tested and backed by our 1 year warranty up to 800fwhp. Nitrous users however are not covered under the warranty due to the instantaneous shock impact nitrous has on the input shaft and forward hub. For this reason, we always recommend nitrous users under 1,000hp to consider a 4L80E with the addition of a billet input shaft and a billet forward hub.

Additional upgrades available

  • RattleSnake Transbrake – $800+pan
  • Aluminum 34 Element Pro Mod drum – $100
  • Aluminum 36 Element Pro Mod drum – $200
  • Chevy SFI Ultrabell – $1,000 (Add $100 for LSx bolt pattern w/ 12 o’clock bolt)
  • Ultra Lightened Internal Rotating Assembly – Call for detail

Level II 4L80E – Starting at $3,750

The level II 4L80E is perfect for nearly all high horsepower street cars and many drag cars as well. The billet input shaft and forward hub ensure reliability during big nitrous hits or high boost runs. This is an extremely stout transmission and we challenge you to find another comparable unit at this price, not to mention our 1 year warranty, up to 1,000 fwhp, provided RPM levels do not exceed 7k. Past this point, a billet mainshaft and especially a 36 element sprag are options to highly consider.

Additional upgrades available

  • RattleSnake Transbrake – $800+pan
  • Aluminum 34 Element Pro Mod drum – $100
  • Aluminum 36 Element Pro Mod drum – $200
  • Chevy SFI Ultrabell – $1,000 (Add $100 for LSx bolt pattern w/ 12 o’clock bolt)
  • Ultra Lightened Internal Rotating Assembly – Call for detail

Level III 4L80E – Starting at $4,950

This is for the serious drag or street racer dynoing well into the 4 digit power range. Intermediate sprag failure worries are a thing of the past with the addition of the 36 element Pro Mod drum, used in high level, professional racing events for years. The level IV includes everything listed in the base build list, a billet input shaft, billet forward hub, a billet mainshaft and the Pro Mod drum. It is rigorously dyno tested before leaving the shop and the warranty covers hard part failures for up to 1350FWHP.

Additional upgrades available

  • RattleSnake Transbrake – $800+pan
  • Aluminum 34 Element Pro Mod drum – $100
  • Aluminum 36 Element Pro Mod drum – $200
  • Chevy SFI Ultrabell – $1,000 (Add $100 for LSx bolt pattern w/ 12 o’clock bolt)
  • Ultra Lightened Internal Rotating Assembly – Call for detail

Level IV 4L80E – Starting at $7,200

This is it. The ultimate 4L80E currently on the market, bar none. Include a host of custom machining as well as custom made billet parts, this 4L80E will out perform any on the market. This transmission has been seen in cars make 1900+HP. Warranty covers labor only for one year.

Level IV includes

  • Cleaned and painted HP Capable Case
  • All new electronics
  • All new bushing and bearings
  • Borg Warner high energy Clutches
  • New Steels
  • Billet input shaft
  • Billet Rollerized forward hub
  • Billet main shaft
  • Billet Overdrive Carrier
  • Billet Oversized Center Support
  • Billet press fit sun tube
  • Billet intermediate pressure plate
  • 36 Element Aluminum promod drum
  • Billet Autoshift Transbrake
  • Increased clutch count throughout
  • Billet intermediate band delete
  • Rollerized Direct Drum mod
  • Custom Pan Baffle
  • -6 AN Cooler Fittings
  • Custom Center support spring Retainer
  • Trans Brake Instant Return Springs