trany upgrade
Here is what I've saved from a previous post from someone named Jeff... BajaGringo
Full-size trucks first received the huge E4OD (Electronic 4 speed OverDrive) transmission in 1989. Internally, it is essentially a C-6 with overdrive added to the front (such as the A4LD is to the C-3) and an EEC controlled valve body.
If it becomes necessary to overhaul your E4OD transmission, you should perform as many updates as possible if it is a pre-1995 unit. E4OD component updates include, as an example, the following items:
Improved (thicker) converter clutch piston (circa 1994), prevents the formation of cracks which relieve fluid pressure from the apply side of the clutch, causing it to slip and even bluing the outside surface of the torque converter in extreme cases. Ensure that your new converter contains an updated OEM or "LuK" brand heavy-duty clutch. This can be difficult, as many torque converter suppliers and remanufacturers may not use this new style of clutch.
Higher displacement front pump (for 1995) provides more fluid capacity for faster engagement of reverse and greater lube flow.
New (for 1994) 4-pinion overdrive planet and input shaft assemblies replace older 3 and 4 pinion units which tend to develop cracks in the carrier under heavy loads.
Center support update kit (for units built from 1989 through part of 1994) replaces wear-prone bushing with a ball bearing and contains a new overdrive stub shaft.
Stronger overdrive clutch cylinder snap ring which will not dislodge.
Revised sun gear and rear case bushings (circa 1992 model year) provide longer wear life and better lubrication.
Four pinion planet carriers (first used in 1992 model year)
New forward clutch friction plates with hardened internal splines cure "chatter" and "no-drive" conditions in E4OD and some later C-6 transmissions.
I will pass along more as I find it. Jeff


