AW-17220743903, GT-K4ZB5X3V
Keep your First-Gen shifting clean and putting power down. CPP Diesel stocks proven parts for automatic 727/518 (A618) and Getrag G360 manual setups, plus NP241 transfer cases, flexplates, deep pans, coolers, rebuild and service items tailored to 1989–1993 D250/D350 & W250/W350.
Explore the full 1989–1993 Cummins catalog for complementary upgrades.
Pick a heavy-duty converter with a modest stall and furnace-brazed fins, such as the BD ProForce or ATS Heavy-Duty.
A performance valve body like the ATS Towing VB or BD 1030410 improves line-rise and clutch apply.
Synchronizers, bearings, forks and select gears (e.g., 3rd gear). Use quality rebuild kits and correct fluid.
Many 4×4 First-Gens use an NP241D. Verify input spline count and speedometer setup.
They help keep ATF cool and extend service intervals. See the ATS Deep Pan and ATS Fan-Cooler Kit, then add a trans temp gauge.