203 vs. 205

[babyburb]

Can someone please explain to me the advantages of the 205 over the 203? I currently run the FT 203 but reading different post most reccomend the 205. Would the 203 rebuilt with a PT kit be a good match up with a 400 to 454 swap and T350 to a t400 swap or should I keep saving and go with the 205 instead. Don't know the difference between the two so I can't make an informative decision.
Thanks

 

[TexasBlazerBoy]

I run the 203/TH350 also. And like you everything I read says to upgrade to the 205/TH400. I know the 203 is chain driven and the 205 is gear driven and supposedly stronger than the 203.

The conversations I heave read about all say why install the part time kit and lockouts/hubs when you can install a 205 and get all of that and a beefier x-case.

With the 203 being full time, most people have no use for this and want to be able to not run full time, hence 205 with hubs and unlocked.

I think with 203 being full time making the front end parts work all the time increases the useage and increases the wear and tear on the front parts meaning more preventative maintence.

In my case I don't need to the part time kit because all I do with my rig is wheel. It sees very few highway miles. No longer than 50 or so for the local play trips.

If any of this is wrong I am sure someone will correct me.

 

[blazinzuk]

Ah the old 203 205 argument, well here is what I think, I would look for a 205, unless you can find a 400 with a 203 already attached to it(your 203 is a 27 spline while turbo 400s take a 31 spline and a different adaptor), then I would just part time it.

The 203 is a good case but can break, now I am not a full time mechanic and have not seen tons of these break but I have seen three of four break, 3 of them had 80/90 gear oil in them, the other one had trans fluid in it. 203s take engine oil, I use 10/30 in mine. I have also replaced a couple of chains in 203s for other folks who swore they were stretched out. One of these chains looked dang near new I used it in another case I built and it is still going strong. The 203 is heavy and long, the cheap part time kit can loosen up somewhat http://www.coloradok5.com/milemarkerpt.shtml read this. I used the shaft kit in mine its great.

205 on the other hand is still heavy although I am pretty darn sure its lighter than a 203 all gear and can with stand alot of abuse. While I am a fan of a 203 there is no decent reason I can see to swap one for the other unless you need a longer rear driveline

 

[BizeeB65]

I swapped my 203 out last year 1) to have 2WD since I drive my K5 everywhere I wheel and 2) cause I couldnt see spending $125 on a part time kit for my 203 which the rear output was shot on when I scored 2 complete 205's with adapters and crossmembers and skidplates for that much.

Now the 1.96:1 low range leave something to be desired in the 205, but knowing its gonna outlast just about everything else on my truck is piece of mind!

 

[Leper]

205 = Cast iron case = beef

 

[76zimmer]

I believe the 203 has a differential unit in it, for use in 4hi for street or hard surface driving, allowing some slippage. The 205 does not, all gear drive.

 

[BUDDY]

Go here
& here
& here
& finally here.

HTH,
Buddy

 

[howdiy]

I grenaded my 203 so I put a 205 in