Full time 4x4 conversion

[K5 Silverado]

Hey everyone I found a 73 Blazer for parts. As I said before the gears in my blazer are off. The one I am looking at is full time. Would the hubs off from mine work or would I have to buy the conversion kit? Also the motor is a well built 350 so I thought about pulling my 350 tbi and droping in the other, is there anything I need to change. Its mated to a 400 will it bolt to my 700 trans also would I be better off just putting the whole set up under mine. My body is okay but the parts blazer I am buying has a great running gear, I dont know which transfer case but I am told that the one in my 87 isnt that tough. So which would be better the well built 350, 400 trans transfer case out of a 73? or the 87 350 tbi 700r and I believe the new process 205?

 

[imiceman44]

Hey everyone I found a 73 Blazer for parts. As I said before the gears in my blazer are off. The one I am looking at is full time. Would the hubs off from mine work or would I have to buy the conversion kit? Also the motor is a well built 350 so I thought about pulling my 350 tbi and droping in the other, is there anything I need to change. Its mated to a 400 will it bolt to my 700 trans also would I be better off just putting the whole set up under mine. My body is okay but the parts blazer I am buying has a great running gear, I dont know which transfer case but I am told that the one in my 87 isnt that tough. So which would be better the well built 350, 400 trans transfer case out of a 73? or the 87 350 tbi 700r and I believe the new process 205?

That 73 has the th400? If it's full time then it has the 203 and if you have any plans in the future for making it extreme crawler and want a doubler you have a good start: th400/203 and all you will need is a old style 205.
Also for off road the 203 is better for now unless you want better mileage for on road if it's a dual purpose rig.
The 700 with 208 from your 87 would be the best for mileage.
And they are not that weak of a setup, just not as strong as the 203 and 205 with the th400.
Confused enough?
As for converting the 203 to part time, you can but you need more than just the locking hubs.
there was a guy selling the complete kit for $100 it's the doug nash single piece shaft which is the best system.
If he still has it jump on it.
My 203 has that kit, but now I am thinking of converting back to fulltime for better all around mild offroad.

 

[tarussell]

I thought the TH400/203 started in 1977/78 ?

Got pic's ?


Tom

 

[K5 Silverado]

Well I took a good look at it today after work. You know I still didnt get the exact year I was told by another guy it was a 72 73 but it looks just like the 77 I use to have its not full tme, just there are no hubs the transfer case has lo loc, lo, hi, hi loc. that is what the shifter says. I was talking to the guys who ownes the truck nephew who told me everything at first, but after work I went and talk to the guy and he told me he doesnt know what trans is in it just that it is a 3 speed. Also it clangs really hard when shifting from reverse to drive is that the crush sleve in the rear end, he told me maybe the u joints. either way slop like that in the rear does it mean that it will go out soon? or just wore? sorry guys about the info being vage but I am thinking about buying it tommrow and then I will have more info and details. also I was so stupid to over look, but are those 6 lug like mine? It had hub caps so I never got around to look at it

 

[chevyin]

Better go online and at least check out the year of the truck. There is a huge difference between a 72, a 73, and a 77. The 72 is a first gen full convertable, the 73 is a second gen full convertable, and the 77 is a second gen half top. Very easy to tell apart.

 

[K5 Silverado]

It only a half top

 

[imiceman44]

Well I took a good look at it today after work. You know I still didnt get the exact year I was told by another guy it was a 72 73 but it looks just like the 77 I use to have its not full tme, just there are no hubs the transfer case has lo loc, lo, hi, hi loc. that is what the shifter says. I was talking to the guys who ownes the truck nephew who told me everything at first, but after work I went and talk to the guy and he told me he doesnt know what trans is in it just that it is a 3 speed. Also it clangs really hard when shifting from reverse to drive is that the crush sleve in the rear end, he told me maybe the u joints. either way slop like that in the rear does it mean that it will go out soon? or just wore? sorry guys about the info being vage but I am thinking about buying it tommrow and then I will have more info and details. also I was so stupid to over look, but are those 6 lug like mine? It had hub caps so I never got around to look at it

If it's a half top it 76 or later.
If it has lo loc, lo, N, Hi , Hi Loc it's a 203.
And for the record, my 73 had a 203.
The 203 is is the only full time Tcase that was offered in the K5
73 was the first year the 203 was offered.
74 was the year only the 203 was offered.

 

[K5 Silverado]

would the gears in the rearends most likely be alot more tall gears? Maybe to much I dont know what it has but I am worried if they are more the 3:73s that with the 32s it will be really gut less cause I have 700 trans and the other is either a 350 or 400.

 

[imiceman44]

would the gears in the rearends most likely be alot more tall gears? Maybe to much I dont know what it has but I am worried if they are more the 3:73s that with the 32s it will be really gut less cause I have 700 trans and the other is either a 350 or 400.

The 76/77 years came in 3.08 and had optionnal 3.73 with the 400 engine and th400, and the HD option with tow package could be had with 4.10.
Only way to know fo sure is to pop the cover or lift one tire and turn it and count revolutions on the drive shaft.

 

[K5 Silverado]

It most likely going to have 3:08s I think so what would the effect be with the 700r trans and the 350tbi. I got 4:11s right now is it going to be a dog really bad?

 

[imiceman44]

It most likely going to have 3:08s I think so what would the effect be with the 700r trans and the 350tbi. I got 4:11s right now is it going to be a dog really bad?

The 700 has a lower first gear and better spread with the gears, but it doesn't like tall gears and tall tires, so unless you drive it carefully and not use the overdrive unless it's really comfortable, the 32's will hurt it.
It won't happen overnight but it will not last long.
32's are not too much bigger than the stock option 31" tires the K5's came with but then again when they started the 700 the standard ratio became 3.42, so 3.73 would be the best for your 32 tires size but I guess if you're not beating it hard it should be fine.