swapping 205 for a 203

[lugnutx2]

I'm taking the 4 speed and 205 out of my 1980 K20 and installing a turbo 400 and 203 unit that I have here in the shop. Since, my truck has factory lockouts, I heard that a shim had to be added when using a 203 with lock outs? If so, can someone give me more details on what needs to be changed? Thanks, Dave

 

[nvrenuf]

Never heard of adding shims to anything.


Is the 203 still full-time or has it been converted to part-time?

If full-time, then the driveshaft will still turn but with the hubs unlocked there will be no power to the ground. If its been converted, you're good to go as is.

 

[lugnutx2]

It's never been apart, so I'm sure it's still full time. How do I convert the 203 to part time operation and I guess this needs to be done when using lock outs?

 

[nvrenuf]

To convert it to part-time there's a kit you'll need that replaces some parts in the differential inside the 203. Once installed (along with the locking hubs you already have) it will behave similarly to the 205.

 

[lugnutx2]

Thanks for the info, I looked up a kit made by Mile Marker, I guess that's the one I'll buy. Thanks again!

 

[bucket]

You don't have to install the part time kit either. You can run with the hubs locked all the time and treat it like a normal 203, or you can shift it to a 'LOC' position and run with the hubs unlocked.

 

[lugnutx2]

Don't the auto "full time hubs unlock at high speeds on a factory 203 setup? Also, I read somewhere on this site that if you ran the 203 in locked position with unlocked hubs that it would eventually damage the transfer case? I'm no expert, been 30 years since I messed with one of these, I thought about a T 400- 205 setup, but they're expensive when you do find them.

 

[bucket]

Don't the auto "full time hubs unlock at high speeds on a factory 203 setup? Also, I read somewhere on this site that if you ran the 203 in locked position with unlocked hubs that it would eventually damage the transfer case? I'm no expert, been 30 years since I messed with one of these, I thought about a T 400- 205 setup, but they're expensive when you do find them.

The full-time hubs were just drive slugs, no locking or unlocking. The 203 has an internal differential that let's it run on the street with a locked front driveline. Running with hubs unlocked and t-case in "loc" won't harm anything that I'm aware of, I've done it for years and so have most 203 owners around here.

 

[hirschdalechevy]

You should try and look around on line , the doug nash 1 piece hub kit in a 203 is way better , (stronger & longer lasting) than the mile marker kit. They dont make them (new)anymore but you might find one.