Description
4L80E / TH400 Heavy Duty Intermediate Clutch Backing Plate, Sonnax 34144HD-01.
When increasing pressures in GM ’98-earlier 4L80-E transmissions, the backing plate can break, the clutch may fail, and case lugs may blow out. The billet steel clutch backing plate 34144HD-01, made by Sonnax, is .375″ thick and heavy duty. It features lugs around the entire perimeter to enhance durability and can withstand higher pressures. This plate can also be used to upgrade the .430″ thick plate in TH400 transmissions, allowing for more intermediate clutch setup options.
- Stronger material and full set of case lugs prevent failure at higher pressures
- Compatible with OE and aftermarket cases
- Use with Sonnax case saver retainer 34762-10 to eliminate OE case lug blow out, no plate modifications required
- Allows for more options when expanding TH400 intermediate clutch capacity
