TH400 Master Rebuild Kit 1965, new and ready to install. Fits the TH400. Ships fast from the USA.
1965 is the year the Turbo 400 spread from Buick and Cadillac to Chevrolet and Oldsmobile, and this master rebuild kit covers that unit and every TH400 built after it. It is our straightforward clutch-and-seal kit: every friction, every steel plate and every seal and gasket needed to overhaul the transmission, without the extras you may already have or may not need. It is the right pick when your 400 slips, engages late, or leaks from several places, and your bands, bushings and modulator check out fine at teardown.
There is no band, bushing, filter or modulator in this kit. If you would rather have a front band, both main bushings, a filter and a new modulator in the same box, the Level 2 TH400 master kit includes them.
The TH400 has three clutch packs, forward, direct and intermediate, plus a front and a rear band, all applied by fluid pressure through piston seals and Teflon sealing rings. When the lining wears thin, clearances open up and the transmission takes longer to apply each clutch, so you feel a flare between gears. When the seals harden, pressure bleeds off and the same thing gets worse when the fluid is hot. Replacing every friction, steel and seal brings the apply circuits back to new condition.
Check the fluid level hot, make sure the modulator is not pulling fluid through its vacuum line, and confirm the shift linkage and kickdown switch are adjusted. If the transmission still slips, a pressure test will show whether the cause is internal leakage or a sticking valve. Our TH400 problems and fixes guide and the TH350 vs TH400 identification guide help you confirm you have a 400 and narrow down the failure.
The kit maker builds this kit for THM400 units from 1965 up, so it covers 1965 and later GM cars, trucks, vans and motorhomes as well as the other makes that used the 400. The listing is filed under 1965, but the contents are the same for later years. Heavy-duty truck units and some performance builds can run different clutch counts, so count your packs at teardown, or send us the year, vehicle and VIN and we will confirm it before you order. Owners of 1965-1967 Buick, Olds and Cadillac cars with the variable pitch converter, marked by the two-prong case plug, can also use this kit for the clutches and seals. Browse every TH400 part on our TH400 transmission page.
Inspect the TH400 intermediate sprag while the unit is apart, and if you want quicker, firmer shifts add the TransGo 400-1-2 shift kit. The TH400 wear points guide lists the hard parts that most often cause comebacks.
| Fits | TH400 1965 |
| Part type | Master Rebuild Kit |
| Condition | New |
| Brand | OEM |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
It is built for TH400 units from 1965 and later, including GM cars, trucks, vans and motorhomes. Count your clutch packs at teardown or send us the year and VIN if you have a heavy-duty or modified unit.
No. It contains frictions, steels, sealing rings, metal clad seals, gaskets, O-rings and piston seals. For a front band, bushings, filter and modulator in one box, choose our Level 2 TH400 master kit.
Yes for the clutches and seals, since the kit is made for 1965-up units. The variable pitch converter and its two-prong case connector are separate parts that this kit does not replace.
Steels warp and glaze from heat, and a worn steel can ruin new frictions. This kit includes a full set of steel plates so you can replace them all.
Have about three gallons of Dexron ATF ready. A dry TH400 with an empty converter takes roughly 10 to 11 quarts plus the cooler, and the final level is set hot on the dipstick.
