When it comes to transfer cases all you really need to worry about is the year, spline count, and the housings. Internally the gears are all the same from 90-96 and from 97-99 they had different ratios. So if you have a trans from a 94 and you find one that is from a 95 then its fine. Manual and Automatic transfer cases were the same gear teeth count and ratio during each of those ranges. You can see below in the ratio section. So when automatic transfer cases to start getting very scarce and you have a broken one with a good front and center housing then you can put the manual internals into the automatic housings and it will work just fine.
The easiest way to identify a automatic transfer case from a manual one is the raised mounting ears on the center section. Though both the front housing and the center section are auto specific. The rear housing is the same as its manual counterpart. You may see variances in transfer case colors. The tail housing and center section will always be silver. If its any other color the part has been powdercoated or painted. The front housing was made in silver and black. The black is cast iron. Referencing the silver color isnt silver, a paint, nor a powdercoat. Its an indicator for the material the housings are made from which is aluminum.
Note: RVR transfer cases use the 97-99 ratio.
|90-96 MT or AT||24/22||1.090|
|97-99 MT or AT||29/27||1.074|
This is the shaft that goes from the transmission to the transfer case. There is a difference in length with these shafts. There are 1G and 2G. If the transmission had lockup then you need the longer 2G shaft. If you didnt have lockup then you need the shorter 1G shaft. The shaft lengths are below. Pictured: Left is 1G, Right is 2G. THESE SHAFTS ARE NOT INTERCHANGEABLE WITH MANUAL!
There are two different spline counts on the transfer case input gear. Early 1G was typically 22 spline and late 1G all the way through 2G years they were 23 spline. You need to run the transfer case based on how many splines your PTO shaft or transmission to transfer case shaft has. You can run different spline transfer cases so long as you swap out the shaft as well.
The automatic transfer case Fluid capacity is the same as the manual transmission fluid capacity.
If your wondering what the best fluid is for your transfer case then please see the link below to Team Rip Engineering. He outlines this well. Team Rip Engineering T-CASE OIL
The transfer case aftermarket is very well supported and still being pushed to its limits and parts being developed.
Transfer case braces are intended to provide more strength on all axis of the transfer case which gives it rigity and prevents deflection as well as any twisting, bending or any other movement on all of its axis. This prevents breakages like busted housings, gear destruction from deflection or case deformation. Its a safe bet that 99% of the people running 9.99 or faster are running a brace. There are 3 different braces to choose from. Magnus Motorsports makes a billet front housing cap that provides extra strength. These were the first brace to hit the market. Some people still run these but there are better options available now. JB Designs makes a thick chromoly steel plate design brace that runs the length of the transfer case. This is a big step up from the Magnus brace. The third is the Frontline Fabrications transfer case brace. It is CNC machined out of billet aluminum and was taken to the extreme. The thickness of the Frontline Fabrications brace should be considered as it does cut into the exhaust tunnel space where it runs right by the transfer case as well and the JB Designs brace is slimmer and does not have this problem.
This is the output shaft also called a transmission to transfer case shaft. This is the shaft that goes from the transmission to the transfer case. This JB Designs shaft is made of 300M. Stock output shafts have been run into the 7s. They dont really become an issue unless they are wore out then they will twist. Some running under mid 8s have twisted the splines while they have also ran deep into the 7s on them as well. This is a 2G drop in and will work in a 1G transmission with JB Designs converter kit.
A common upgrade to prevent failures was the 25 spline 300m transfer cause output shaft. These do NOT fit with a stock driveshaft and is something that requires a larger yoke for the bigger shaft with more splines to connect to an aftermarket driveshaft. When you get to the point to where you need a 25 spline 300m transfer case output shaft you should already have a aftermarket driveshaft anyway. They also require permanent removal of the dust sheild. At a point the stock transfer case output shaft becomes a weak point especially when you try to 60 foot the car hard which usually is to much torque or deflection. This combats both of those.
Magnus has developed and released the transfer case billet gearset. This is a major hurdle as the transfer case has been a weakpoint for a while now since automatic DSMs have dipped into the low 7 second quarter mile. This will ensure reliability and strength within the transfer case to deliver consistent low 1 second 60 foots. This is most definitely one of the keys to long lasting tcases under high performance and definitely is part of the recipe for a bulletproof tcase. This is compatible with the Boostin center housing and of course the Magnus Motorsports Billet front housing. For more information or to purchase then reach out to Magnus Motorsports.
Magnus transfer case housing is crucial for anyone who wants to go fast with their DSM or EVO I-III. With over 20 years of experience racing these vehicles, we have come up with a product that will survive all the abuse you can throw at it. Made out of 7075 Billet Aluminum, these housings are immensely stronger and lighter than what Mitsubishi had originally offered. The product is race proven on 7 second DSM’s.
Boostin Performance makes a billet transfer case center section. Currently no automatic car is running these to my knowledge its just manual cars. It is claimed that this increased longevity 3x over a stock center housing. Its said that the OEM cast aluminum center section is weak and does flex under load. This product is designed to eliminate flex in the center housing, eliminate gear deflection, and it keeps the gear tooth pattern correct under all load scenarios. They are made from 6061-T6 billets of aluminum. Boostin recomends using these at anything over 600HP. These are made for automatic transfer cases and they are compatible with all of the transfer case braces.