The Tremec T176 transmission was a four-speed transmission used in Jeep vehicles from 1980 to 1986. The transmission is largely considered as one of the better transmissions offered by Jeep during the 80’s. The transmission was used behind the inline 258 engine as well as the AMC 360 V8. The T176 makes a suitable candidate for moderate V8 engine conversions. The T176 transmission was one of 4 manual transmissions used during 1980-86. It is considered relatively stout for its compact size. The T176 can easily be identified from the T4, SR4 and T5 by the shifter coming out of the aluminum top cover rather than the tail housing section. The aluminum top cover is retained by 10 bolts.(see photo) The main case is also cast aluminum. The transmission case length is 10.25" long and used short 2.62” tail housing. The transmission case has casting numbers located on the driver side of the transmission. We have seen a series of casting numbers used. The numbers seem to be a sequential series starting with C-2604203 through C-2604208. The Jeep T176 has a 23 spline output shaft for connecting the transmission to the transfer case. The stick out length for the transmission input is 7-1/2" with 1-1/8" 10 splines. The pilot tip is .59” in diameter. The T176 utilizes a standard 4-H shift pattern with reverse located down and to the right. The T176 is a top loaded, top shifting transmission and is synchronized in all forward gears. The transmission is well engineered and features all helically cut gears. The T176 does not have a compound low gear but does have all around good gearing ratios of:
- 1st gear 3.52:1
- 2nd gear 2.29:1,
- 3rd Gear 1.46:1
- 4° Gear 1.00:1
- Reverse 3.52:1
VARIATIONS The T176 also had a couple different offshoots known as the T177 and T178. These were basically the same transmission as the T176 but with minor variations. The T177 and T178 were commonly used in J Series trucks and wagons. The transmissions themselves were not necessarily stronger; rather their variations were more based on gear ratios, input shaft lengths and rear bolt pattern rotations. The T177 and T178 used significantly longer input shafts and a bell housing spacer of 2.75”(see photo) was used to compensate for the deeper engine compartments on the full size Jeeps. The gearing differed as well. We have seen the following gear ratios: T177 3.82, 2.29, 1.46, 1.00 R3.82 T178 3.00, 2.08, 1.47, 1.00, R3.01 Caution should be used when obtaining a T177 or T178 for conversions. The longer inputs normally have to be changed for most engine conversions. As a general rule, any time an input shaft needs to be changed the cluster it meshes with must have the same tooth count. Since the T176, T177, and T178 have varying first gear ratios, their cluster gears also varied, for example we have seen cluster gear tooth counts of 19, 20 and 22. It is therefore critical to select the shorter input transmissions if an engine conversion is desired.
V8 CONVERSIONS The T176 transmission is well suited for mild to moderate V8 conversions. The transmission is relatively stout and seems to handle V8 well. It is considered a medium duty transmission; however, so horsepower and tire size may dictate upgrading to a more heavy duty transmission at some point. The front bolt pattern of the T176 takes many by surprise. The transmission actually shares the same bolt pattern as Ford. This bolt pattern is commonly referred to as the Ford butterfly bolt pattern. It measures 8.5” (top side to side) x 6.3” (top to bottom) x 9.25” (bottom side to side). This common bolt pattern clearly offers a relatively easy route for bolting a ford 302 to the T176 by factory ford bell housing. The difficulty in this conversion lies in the fabrication required to retain the factory clutch pedal configuration. The Chevy V8 conversion is more popular and the Advance Adapters bell housing allows for the retention of the factory clutch pedal configuration. Since we use the same bell housing for Chevy to Ford applications, customers who choose to use this bellhousing for the T176 have the opportunity to upgrade to other transmissions. This bellhousing will also bolt up to popular truck transmissions like the Ford T18 and NP435. Advance Adapters also offers a plate design to use with a factory Chevy bellhousing. The kit offers a slight savings in relation to our full bellhousing; however, an additional kit is required for retaining the clutch pedal linkage. In 1986 Jeep retired the CJ7 in favor of the YJ Wrangler. The new Wrangler would also see the introduction of a new series of 5 speed transmissions and with it the discontinuance of the T176