TH350 valve body for 1969-1986, OEM and ready to install. Ships fast from the USA.
If you're building a TH350 for drag racing or bracket racing and want full manual control over every shift plus a transbrake for consistent launches, this billet CNC valve body (PCE634) replaces the stock hydraulic unit in 1969-1986 TH350 applications with a full manual valve body and integrated transbrake.
A stock TH350 valve body shifts automatically based on throttle position and vehicle speed, which is exactly what a racer doesn't want - inconsistent shift points cost tenths at the track. A full manual valve body removes that automatic logic entirely: you select 1st, 2nd, 3rd, Neutral, and Reverse directly with the shifter, and the car stays in whichever gear you put it in regardless of RPM or speed until you move the shifter again. The transbrake adds a hydraulic circuit that locks the transmission in both 1st and Reverse simultaneously when you hold a button, letting you load the converter against the brake at full throttle on the starting line and launch the instant you release it.
A full manual valve body with transbrake is a racing part, not a street-driven comfort upgrade - it requires you to shift every gear yourself and trusts you to manage the transbrake button correctly, so it's the wrong choice for a daily driver. If your TH350 is just shifting harsh or slipping on a street car, start with our TH350 valve body problems and testing guide to diagnose the stock unit before spending racing-part money on a street fix.
This valve body is built for the TH350 as used in 1969-1986 GM applications - Chevrolet, GMC, Pontiac, Oldsmobile and Buick cars and trucks. Full manual valve bodies are built to the case and bolt pattern of the transmission generation, not the specific vehicle, so confirm you have a genuine TH350 (not a TH350C with lockup converter, which needs different provisions) before ordering; the TH350 parts collection has the rest of what we carry if you need to cross-check. For background on how this transmission is built, see our TH350 gear ratios and specs guide.
Because this valve body changes the shift pattern entirely, you'll need a compatible shifter with a gate for manual 1-2-3-N-R and a separate transbrake button wired to the brake circuit - this is a transmission-only listing, so plan the rest of the control system before install day. Set up the transbrake line pressure and the manual valve detents per the instructions included with the unit, and cycle the shift pattern on a lift before you trust it at the track. Run fresh Dexron ATF and a new filter at install, and if you're already tearing into the transmission for this swap, it's a good time to check the TH350 sprag clutch and inspect the input drum for wear, since both are common failure points under repeated hard launches.
| Transmission | TH350 |
| Year Range | 1969-1986 |
| Condition | Remanufactured / updated |
| Shipping | Ships from the USA |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
You can, but you'll be shifting every gear yourself with no automatic failsafe, and the transbrake button requires correct use every time you stop - most people reserve this setup for a dedicated race car.
This is built for the standard TH350 case. A TH350C has different provisions for the lockup converter circuit, so confirm which version you have before ordering.
A shifter with a manual gate (1-2-3-Neutral-Reverse) and a transbrake button wired into the brake circuit; this listing is the transmission-side valve body only.
Dexron ATF, same as the stock TH350, with a fresh filter at install.
The sprag clutch and input drum take the brunt of repeated hard launches, so it's worth inspecting both while the transmission is apart for this install.
