eggman918
Adventurer
When i did the Cummins swap in my Highboy I did my best to optimize my gearing for highway mileage 33" tires 3.55 gears it worked well and I average 20mpg double what i got with the 390,but it left me with trail gearing that was far from ideal. Initially I was running the M5odr2 with a ~4-1 first gear and a reverse that's worse so a low range lower than 1.96-1 was needed,the '68's frame is too narrow for the chain drive T cases that have lower ratios and I wanted to keep the 205 in the factory configuration so my choices were limmited.
The tech folks at ORD were the only ones that were willing to spend the time with me to decide what was needed to do a divorced doubler,and the final solution was quite simple.
My 205 case was from a '76 F-250 and the face of the case where the input goes had been machined at the factory so all I needed to do was bore the case for the big bearing and drill and tap case for the big bearing's retainer any good machine shop should be able to do it in 2 hours labor if they want more they don't want your work.
the internal core for the T case is the same for both the married and divorced castings,you can see the boss's cast in for the taped holes for the larger bearing retainer as well as the extra thickness for the big bearing.
I picked up a married input shaft/retainer for ~$50.00
Here it is set up on my little mill for the boring opp.
Here the big bearing is in and case is drilled and taped for the retainer
Next is the 203 range box and ORD adapter.
203 and adapter bolted up.
203 205 bolted up.
My shifter solution.
in truck with intermediate shaft in.
Shift linkages
I went with 1350 U joints for the intermediate shaft and rear shaft,the front was new just before the swap so its still factory but I plan D60 front upgrade as soon as i can find one that isn't $1500.00 + and will go to 1350's for the front then.
I have 25,000 miles on swap so far but I killed the M5odr2 towing too much in OD and have since installed a ZF s5 42 it was ~ 6" shorter than the M5 but the M5 had a slip yoke and the ZF has a fixed yoke so I ended up with the intermediate shaft being 11.375" from the center line of the caps in the running position.
the 203 shifts very smoothly and is used all the time even with the ZF's lower 1st and reverse when backing and in parking lots and on trails double under is great on rougher trails when we have our camp trailer hooked up my clutch should last for ever.
My only complaint is that I wish at the time I was looking for a doubler there was a planetary unit for the divorced configuration but all in all I am happy,but I have since found a planetary box and an tinkering with it and may eventually build one..........
Link to all pics of this project http://s1042.photobucket.com/user/eggman918/library/Divorced np 203 205 doubler?sort=2&page=1
The tech folks at ORD were the only ones that were willing to spend the time with me to decide what was needed to do a divorced doubler,and the final solution was quite simple.
My 205 case was from a '76 F-250 and the face of the case where the input goes had been machined at the factory so all I needed to do was bore the case for the big bearing and drill and tap case for the big bearing's retainer any good machine shop should be able to do it in 2 hours labor if they want more they don't want your work.
the internal core for the T case is the same for both the married and divorced castings,you can see the boss's cast in for the taped holes for the larger bearing retainer as well as the extra thickness for the big bearing.
I picked up a married input shaft/retainer for ~$50.00
Here it is set up on my little mill for the boring opp.
Here the big bearing is in and case is drilled and taped for the retainer
Next is the 203 range box and ORD adapter.
203 and adapter bolted up.
203 205 bolted up.
My shifter solution.
in truck with intermediate shaft in.
Shift linkages
I went with 1350 U joints for the intermediate shaft and rear shaft,the front was new just before the swap so its still factory but I plan D60 front upgrade as soon as i can find one that isn't $1500.00 + and will go to 1350's for the front then.
I have 25,000 miles on swap so far but I killed the M5odr2 towing too much in OD and have since installed a ZF s5 42 it was ~ 6" shorter than the M5 but the M5 had a slip yoke and the ZF has a fixed yoke so I ended up with the intermediate shaft being 11.375" from the center line of the caps in the running position.
the 203 shifts very smoothly and is used all the time even with the ZF's lower 1st and reverse when backing and in parking lots and on trails double under is great on rougher trails when we have our camp trailer hooked up my clutch should last for ever.
My only complaint is that I wish at the time I was looking for a doubler there was a planetary unit for the divorced configuration but all in all I am happy,but I have since found a planetary box and an tinkering with it and may eventually build one..........
Link to all pics of this project http://s1042.photobucket.com/user/eggman918/library/Divorced np 203 205 doubler?sort=2&page=1
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