High-performance Bowler Tru-Street 4R70W transmission and converter for Small Block Ford engines making up to 420 lb-ft. Built with premium components, recalibrated valve body, stronger internals, upgraded lubrication, and fully dyno-tested. No controller or accessories included.

If you're running a Small Block Ford and you want a transmission that actually handles real power, survives real street miles, and delivers real performance, this is the 4R70W you buy. No gimmicks. No repackaged stock build. No “mild street upgrade.” This is Bowler’s Tru-Street Series, engineered for people who want to DRIVE their cars—not babysit them.

If you want reliability, repeatability, shift quality, and a transmission that can take abuse without complaint… this is your transmission.

What You’re Actually Buying

A professionally engineered 4R70W built for Small Block Ford engines up to 420 lb-ft of torque, designed to outlast and outperform anything in its price range.

Includes:

Bowler 4R70W Performance Transmission
1800–2000 rpm Stall Single Disc Lock-Up Converter
Electronic speed sensor (mechanical available—ask us)
Complete Bowler inspection + dyno test
90 Day limited/conditional warranty
No core required

Does NOT include:
Controller, fill tube, cooler, yoke, driveshaft, flexplate, crossmember, fluid, or accessories.
(We recommend our Tru-Street Installation Package.)

Why This Transmission Exists

Because SBF owners deserve a transmission that actually supports modern builds.
You’re not building a car for Sunday parking-lot cruises—you want something you can put real miles on while enjoying crisp shifts and dependable performance.

This unit is built to do EXACTLY that.

Inside the Build (This Is What Makes It Better)

All-new clutches, steels, seals & gaskets
New OEM solenoids (EPC, TCC, PWM, shift solenoids & MLP sensor)
Pro Series wide OD band for increased surface area
Updated molded 2–3 accumulator piston
Increased line pressure for firmer, more durable clutch engagement
Recalibrated valve body for improved shift control
Updated bypass valve + pressure regulator valve
Stainless steel sun shell upgrade
New Torrington bearings
Improved lubrication circuit for better thermal stability
Updated mechanical diode intermediate sprag
All-new thrust washers
New OEM steel pan

This isn’t a rebuild—it’s a re-engineered, performance-first, reliability-focused transmission system.

Who This Transmission Is For

SBF-powered street cars
Restomods
Street/strip builds
Weekend cruisers that still want hard pulls
Daily drivers requiring reliability
Builders who want Bowler-level consistency and quality

If you want cheap, this isn’t it.
If you want dependable, dyno-tested performance you never have to think about, this is exactly what you buy.

Lead Time

Approx. 4 weeks for assembly and dyno testing.

Fitment Notes

Specifically designed for Small Block Ford engines
Will NOT fit FE, big block, modular, or Coyote engines
Mechanical speedometer output available—contact us
Use with recommended Bowler Tru-Street Installation Package or equivalent components

** We recommend our Tru-Street Installation Package or you can source all of your own installation items

Install Guide

Bowler Tru-Street Ford 4R70W Performance Transmission and Converter Only for SBF Engines (Up to 420 lb-ft of Torque)

Bowler Tru-Street Ford 4R70W Performance Transmission and Converter Only for Coyote/ Modular engines (Up to 420 lb-ft of Torque)

Tru-Street Ford 4R70W Performance Transmission for Coyote/Modular engines (up to 420 lb-ft torque)

Tru-Street Ford 4R70W 4x4 Performance Transmission for Coyote/Modular engines (up to 420 lb-ft torque)