how much longer is a 203 vs. a 205?

[Cornfield creations]

I was thinking about swapping a np 205 in place of my np203. My blazer is a 79 and the transfer is coming out of a 72. How much shorter is the 205? Also, I already have a HAD shaft, would my 203 drive flange work on a 205? I don't know if the rear output shafts are the same or not.
Thanks in advance guys!

 

[pauly383]

I have both I can photograph when I get home . But I figure at least almost the width of the 205 itself . The 203 has a rangebox and a tailhousing . The 205 is almost as thick as just the 203 middle , with yokes on each side

 

[diesel4me]

my swap...

I put an NP205 in place of a NP203 in my '74 K20..only the front driveshaft didn't fit,it was too long,had to find one from a '69 GM 4x4,the only year they had a "shorter" front shaft factory,and it fit perfect....the rear shaft bolted right up fine..so I think the only difference is the front half of the NP203 is farther away from the front axle than a NP205 would be..

Of course,trucks DO change slightly from year to year--mine was an abortion of several trucks combined into one..had a '77 frame,and '85 axles,bed,and doors,etc..depending on what tranny,adapter,crossmember etc,you may find it won't work out as easy as my swap did..only one real way to find out--start wrenching!..

 

[1979jimmy350]

well another option you have is to combine the two, a doubler is about the same length as the 203 and then you get all gear and can use the current shafts

 

[dbozman]

Just swapped the 203 in my '74 for a 205 (behind a T350). I have CV shafts on both ends. The rear had to be lengthened roughly 3(ish) inches if memory serves and front shortened about the same 3 inches. I was able to use the rear output yoke from the 203 on the 205 to make with my CV joint, just had to get a different seal from Carquest.