Borg-Warner SR4

The Borg-Warner SR4 Transmission was a standard shift, 4-speed transmission found in 1980 and 1981 Jeep CJs. It is a light duty transmission, and was placed behind the 151 Iron Duke I4, AMC 2.5 I4, and AMC 258 I6 engines.

Due to it being a light-duty transmission, the SR4 currently does not have much aftermarket support or adapter assemblies to mate to different engines.

The SR4 transmission case is 9.25″ long in addition to it’s 6″ long shifter/tailhousing assembly. The transmission is fully synchronized in all gears except reverse and all gears are helical cut.

Contrary to a lot of online information, the SR4 does actually have a drain bolt, but it is located in an awkward spot and is one of the bolts used to hold the shifter assembly on.

Gear Ratios – Inline 4 Engines

Reverse3.95
1st4.07
2nd2.39
3rd1.49
4th1.00

Gear Ratios – AMC 258 I6 Engine

Reverse3.39
1st3.50
2nd2.21
3rd1.43
4th1.00

Fluid Type and Capacity

Lubricant80W-90 GL3 or GL4
75W-90 GL3 or GL4
Capacity1.5 qts (1.4L)
Avoid GL-5 lubricant, which can cause increased wear on the brass synchros found in this transmission

Other Specifications

Weight60lbs
Length15.25″
Input SplinesAMC 258 I6: 10
GM 151 I4: 10
AMC 2.5 I4: 14
Output Splines23

Transfer Case Compatibility

The SR4 transmission was found attached to the Jeep Dana Spicer Model 300 transfer case.

Bellhousing Compatibility

The transmission fits factory behind the AMC 258 I6, GM 151 I4, and the AMC 2.5 I4.

The transmission bellhousing will mount up to the Chevy V8s. This conversion requires the smaller GM flywheel, mini high torque start, and modifications to the bellhousing. Advanced Adapters offers a bellhousing (P/N 712548) with multiple holes to allow the mating of the SR4, T4, T5, T150, and T176 to GM V8 engines.

Write-ups and Tutorials

To Be Completed

Parts and Fluids

Engine Fluids

EngineFluid TypeCapacity
AMC 2.5L I4Above 0°F: 10W-30
Below 60°F: 5W-30
4.0 qts
AMC 4.0L I6Above 0°F: 10W-30
Below 32°F: 5W-30
6.0 qts
GM 2.5L I4Above 0°F: 10W-30
Below 0°F: 5W-30
3.0 qts
Renault 2.1Ltbdtbd
VM Motori 2.5Ltbdtbd

Transmission Fluids

TransmissionFluid TypeCapacity
Chrysler A904 3-Speed
Aisin-Warner AW-4 4-Speed
Chrysler 30RH 3-Speed
Borg-Warner T-4 4-Speed ATF Dexron II1.75qts
Aisin-Warner AX4 4-Speed75W-90 GL3 or GL4
10W-30 Motor Oil
2WD: 3.7qts
4WD: 3.5qts
Borg-Warner T-5 5-SpeedATF Dexron II1.75qts
Aisin-Warner AX5 5-Speed75W-90 GL3 or GL4
10W-30 Motor Oil
2WD: 3.7qts
4WD: 3.5qts
Peugeot BA-10/5 5-Speed
Aisin-Warner AX15 5-Speed75W-90 GL3 or GL4
10W-30 Motor Oil
2WD: 3.32qts
4WD: 3.27qts
New Venture Gear NV3550 5-SpeedMopar MT Fluid
SAE 30W Oil
3.3qts

Axle Fluids

AxleFluid TypeCapacity
Dana 3075W-90
75W-140 (towing)
1.26qts
Dana 3575W-90
75W-140 (towing)
1.75qts
Dana 4475W-90
75W-140 (towing)
2.00qts
Chrysler 8.2575W-90
75W-140 (towing)
2.11qts

Transfer Case Fluids

Transfer CaseFluid TypeCapacity
NP207
NP228/229
NP231
NP242

This will close in 0 seconds

4.0L

This will close in 0 seconds