CT - This is an extension housing rear seal and bushing kit. Works with a R4 transmission or a THR Transmission, Made in USA. Always FAST & FREE USA SHIPPING! For questions or to place an order by phone, please call our solutions desk at8AM-6PM PST (West Coast USA). Or Email us using our CONTACT link above.5/5(2). The R transmission will fit all GM motors that have full size bell housings. This is a perfect choice, if you have a non-Chevy motor. You can expect a 30 to 40% increase in gas mileage (over a 3-speed) on the road.
Every Transmission Tested on the PATC Dyno. Good for motors up to horse power using pump gasoline, see chart below. Jan 09, The R is a 4-speed automatic overdrive transmission by GM, capable of fitting into most Chevy’s from the 80s and before, built similarly to the TH and TH, as well as the 2-speed Powerglide transmission.
Build with a torque converter lock, a spline input/output shaft, quart fuel capacity, a case length of about 27” and a Estimated Reading Time: 6 mins. Oct 24, Sonnax Transmission parts for GM R applications. Sonnax is an industry leader in the cutting edge design, manufacture and distribution of the highest quality products to the automotive aftermarket, commercial vehicle industries, and industrial sectors utilizing drivetrain technology. THR Performance Transmission for,,Chevy, Buick, Oldsmobile, or Pontiac V8Brand: JEGS.
The THR is a great overdrive transmission that has received a lot of attention. While some disagree, it is basically as strong as a R4 and will bolt to virtually any Chevy, Pontiac, Buick or Olds Motor with few modifications. The THR has a ratio in first gear, which is 10% lower than most transmissions.
The overdrive will give a 22 to 33% increase in gas mileage.