np203 some are better than others

[chris walker]

what is the difference between the hd diff and the normal diff in the np203 and the two different chains and what years came with the better versions is the chain interchangable?

 

[Confedneck79K30]

never knew there was different hd and non hd, ttt for ya

 

[tarussell]

what is the difference between the hd diff and the normal diff in the np203 and the two different chains and what years came with the better versions is the chain interchangable?

The diff part changed at some point but I did not know one was considered stronger than the other. The chain and sprokets are wider on certain applications and are usually the more sought after items. Usually Blazers and K-10's will come with the slimmer chain and K-20's & K-30's will offer the wider pieces - but I would not go by that rule since the last 203 was made in the late sevety's and who knows what has been replaced by now.

Tom

 

[chris walker]

thanks

 

[4X4HIGH]

what is the difference between the hd diff and the normal diff in the np203 and the two different chains and what years came with the better versions is the chain interchangable?

Doesn't matter, the reduction box is bullet proof and used for doublers. Throw the rest away and forget about it.

 

[blazinzuk]

this is just what I have taken apart. My 73 has the wider chain in it. I was told by one person that if you have the cast iron tailhousing its the wider chain. All the ones I have taken apart that are aluminum tailhousings have the other chain. The differential difference is in how much material is around the spider gears. The older design (I think 76 and older) is substantially beefier than the newer design. So if I were looking for a 203 I would find one with a cast iron tailhousing cause of the very few things that changed these seem to have the strong parts.

 

[chris walker]

so early 70's thanks