Interesting stuff here...
TSB No. 3-03 02159(R)
Subject: Transfer Case Gearbox Case Replacement
Model: Samurai
Year: 1986-1987
When replacing the transfer gear box case assembly on a 1986-1987 vehicle, it is necessary to replace the reduction shift fort. The case was modified beginning with 1988 vehicles. The new shift fork retorfits in the 86-87 case. (But not the other way around).
TSB No. 3-05 08070
Subject: Modification of Transfer Case and Reduction Shifting Fork
Model: Samurai
Year: 1988 and later (beginning 6/87)
this is to inform you that:
1. Transfer case dimensions at the gearshifting shaft bore has been modified
2. The reduction gearshifting fork dimensions have been modified,
3. Transfer case oil filler and drain plugs have been modifed.
(My note: According to the illustrations, the shifter bore are different and have different clearences.)
TSB No. 3-06-08070
Subject: Modification of Transfer Case Gear Shift Control Lever
Model: Samurai
Year: 1988 and later (beginning 12/87)
My Note: Has an illustration of the shifter lever, and the bottom "nub" is way different. The early ones are rounded like a pill, the later ones are very rectangular, with hard corners. It states that the later can be used in the early cases, while the early design is NOT INTERCHANGABLE with the late cases.
I sure hope all the twin stick designers used the post 88 t-case shifters to model their designs from.
TSB No. TS-3-10 08211
Subject: Modification of Differential Bevel Pinion and Flange
Model: Samurai
Year: April 1991 and later
Ny Note: from this date forward, the splines on the pinion are beveled, and INTERCHANGABILITY IS NOT OKAY. I guess adding small bolt flanges on a Kick gear set is a no-no.
TSB No. 3-12 12131
Subject: Modification of Speedometer drive and driven gears
Model: Samurai
Year: 1992
My summary: Drive gear dimensions are the same, heat treatment changed though. However, speedo driven gear and housing HAVE BEEN MODIFIED and dimensions have changed. Interchangability? Late drive and driven gears can go into early, but not the other way. Housings are not interchangable either way.
TSB No. 3-13 01493
Subject: Modification of Transfer Case Gear Shift Locating Parts
Model: Samurai
Year: August 1992 and later
1) Transfer case - depth of locating hole modified
2) Front Drive shift shaft - locating ball groove reshaped (from 65* to 70*)
3) Gear shoft locating inner spring - new addtion of second spring that sits inside existing spring
Interchangability? Late fist early, but NOT the other way. Inner spring can be used only if the new (late) case and front drive shaft are used
TSB No. 3-14 09164
Subject: Modification of Rear Diff Thrust Washer
Model: Samurai
Year: January 1994 and later
HA! This is why you can't install a locker in the rear of a 1994 or 1995. No interchangeability. What it doesn't say is because the SIDEGEAR changed (been there, got the t-shirt)
Lots of other tid-bits too.
Did ya know the ring gear bolts changed and are not interchangeable?
How about the 1993+ Cam and crank pulley mods?
Cam and Valve rock mods, including different heights? Parts can not be interchanged except as a whole.
That 1994 and later got completely different LARGER calipers and mounts (they look like Sidekick calipers)? Huh...
And I haven't even gotten to the Sidekick section yet. Yea! Fun reading for Timmy!
