I want to swap T-cases in my 71. It has a 427/th 350/205 and I need to drop more wieght for this race season. I want to put in a 208 but cant remember if the trans output shaft needs to be swapped out for a longer one. Anyone know?
CK5
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Th350/np208
- Thread starter 468k5
- Start date
th350 to 203 or 205 same shaft.
th350 to 208 or 241 same shaft.
the 203 to 205 is shorter than 208 to 241.
and i dont like first style 208 cases as to to many blowing up.
i would find a other way to drop weight my self first than loose a 205.
acording to shipping weights its 78 lbs for 208 and 130ish for a 205. so not much there in mass but lot more in strength on 205 over 208 if you ask me.
th350 to 208 or 241 same shaft.
the 203 to 205 is shorter than 208 to 241.
and i dont like first style 208 cases as to to many blowing up.
i would find a other way to drop weight my self first than loose a 205.
acording to shipping weights its 78 lbs for 208 and 130ish for a 205. so not much there in mass but lot more in strength on 205 over 208 if you ask me.
I'm not worried about strength I think it will hold up just fine. The truck only wieghs 3500lbs now and just under 500 hp. My trail truck is over 6500lbs. running a tbi454 700r4 np208 5.13:1 gears rolling on 40's and has handled every hole,hill, and rock I have pointed it at without fail for 2 years!
So why can't an output shaft extension (or "coupler", if you will) be machined for this purpose? It would be nice to bolt a common 208 and adaptor to the tail of an also common TH350. I'm no machinist or engineer, but I don't see why it wouldn't work.
I believe it is a longer output shaft for 208/241. The info is one here if you search around. I know there are some posts from me when I was doing the swap. I run a Th350/241 combo, but the tranny was from a K5 with the TH350/208 combo so i didn't have to do anything.
1981 was the only year the th350 and 208 were married, the shaft is longer than the 205 shaft but shorter than a 2wd th350 shaft.
I do have the correct adapter but not the tranny.
I will be doing some measurements to see if the 2wd can be cut and made to work, if it has enough length in the splines since it is a slip yoke.
I will let you know soon.
79rustyk10
3/4 ton status
Thank You, I was just thinking about this whole idea the other day, as I want to get rid of my 203.
