Need upgraded running gear advice.

[ellero]

Ok, so every time I take her out sahe comes home on a flatbed. Thanks again to the AAA driver that knows me by name. Anyway, I have a few problems that I hope to get good advice on.

First, I keep snapping the front U-joint on the rear axle and cant run in FWD due to the rear yolk sliding out and it losing fluid. How do I fix this or can I?

Second, with the 4 inch suspension lift, the fron driveline flexs under load due to it being too short. This I know needs to be replaced.

Third, most all of the front diff oil has poured out the sides of the front axle. Did I break it, or are the seals just gone? How hard is that job?

Fourth, Also on the last trip there was a loud snap and all the tranny fluid was lost. Turns out that the x-fer case is still attached to the tranny, but the tranny housing tore and I have a 1/4 gap about 3/4 around the tranny so the tranny case is done for sure. Needing a new tranny is a given here.

Now I think this is a sign saying sell the truck or upgrade to 1 ton running gear. This is where I am looking for help. I am on a bit of a budget but I am tired on not being able to drive my rig home. If I do the 1 ton swap, what am I in for as I am not a mechanic.

Does anyone know if the 1 ton x-fer case has the yolk on it or if it is in the rear driveline on the 1 tons. If it is on the driveline that solves problem # 1. If it does not, how do I fix problem # 1? Also is it a direct bolt on to the 84 K5 blazer?

What transmission should I look into getting, and why would the outer casing tear in the first place? Is there a special trans / x-fer case combination that I should get because my x-fer case works, but it always slips out of 4H under load? Could it be ok, and just be a linkage issue? My 5.7 L is not modified at all but a more powerfull motor may be in the plans in a year or 2. I would like to have something stronger now so when I do the moter in the future, thats all I will need.

Getting 1 ton axles are a givin as my K5 does see a bit of air from time to time. My hopes are that if I get 1 ton axles, drivelines, transmission and x-fer case that it all bolts together easy and is then bulletproof. It is a lot of $$$, so can I do it in stages or am I hosed. My rig has been down since new years and it sucks. Please help.

John

 

[spoolnaround]

What is your current trans t-case? 700/208? What tire size?
The one ton stuff seems like a good idea for you. It sounds like you like to beat the crap out of your junk. Consider a 4 speed set up? Its a good idea to not treat a Blazer like its a dirt bike, air time isnt kind no matter what you have under it.

 

[spoolnaround]

1. A FF or a SF 14 bolt will fix that.
2. Re tube
3. Prob needs new seals
4. new trans




1 ton transmission is a TH400 for the auto and an SM465 for the 4-speed. NP205 is a 1 ton TC. Some 205's came with fixed yoke (early pre 80), all 1980 came with a 205 not sure if they all had slip but I know the 1/2 tons did.

It looks like you are running 35's, put a SF 14 bolt in new trans and quit jumping it .

 

[ellero]

I just picked up a used transmission / t-case out of a 78 blazer. Not sure what it is just yet, but the TC is much much larger than the original 84, and the 78 set up is a fixed yoke. If its huge and heavy as hell is it a good bet its a 205? Where would I find the model number on it?

John

 

[87BrnRsd]

I just picked up a used transmission / t-case out of a 78 blazer. Not sure what it is just yet, but the TC is much much larger than the original 84, and the 78 set up is a fixed yoke. If its huge and heavy as hell is it a good bet its a 205? Where would I find the model number on it?

John

If it came out of a 78 blazer then its a 203. Huge and heavy as hell are words to describe the 203. There should be a round metal piece on the back of the tranny near where the driveshaft bolts up that identifies the t-case. My bet is that its a 203. Its a cast iron t-case and weighs like 250 lbs. Its a standard (old) half ton t-case but is a hoss. I have seen a guy around here with no skid plate, use the 203 as a skid. In the battle it faced with a large rock, the 203 won....
-Harrison

 

[Hogback Fabrication]

Also, I suspect your lift in the rear is from blocks. I would suspect that is why you broke your driveshaft u-joint. I would ditch the blocks and get real springs as well. On a seperate note, if you are going through all the trouble of swapping in a new transmission and transfer case, I wouldn't bother putting a 203 in. Find a 205 and/or a transmission with a 205 behind it and go with that.

 

[ellero]

Also, I suspect your lift in the rear is from blocks. I would suspect that is why you broke your driveshaft u-joint. I would ditch the blocks and get real springs as well. On a seperate note, if you are going through all the trouble of swapping in a new transmission and transfer case, I wouldn't bother putting a 203 in. Find a 205 and/or a transmission with a 205 behind it and go with that.

I dont have much $$$ to put into it so I am just doing what I can to get it back on the road. I would so much rather take the time and build it super strong, but I hit a financial rock and just need the truck to run for the time being. Also the lift has no blocks. I went with all 4 new springs. I think its due to running 35s at 8 lbs without having the gears done yet, but thats just a guess.

John

 

[goldwing2000]

Go for the 205 t-case. That's a given. If you can't find one with a fixed rear output, you can get the fixed yoke parts off e-bay for around $100.

You can save some money (at least $1000) by going with 3/4-ton axles instead of 1-ton. You'll have the same strength in the rear but the front will still be a 10-bolt (or D44), just with 8-lug hubs and bigger brakes. I wouldn't go any lower (numerically) than a 4.10 with 35s.

Front axles seals are a pain in the ass. The differential case has to come out to get to the seals.