I just bought an 84 K20 Suburban with the 6.2 Diesel. She has the Corporate 10 bolt up front and the Corporate 14 bolt (smaller ring gear version) in the back. The transfercase is the NP208 attached to a TH400. How are these axles? The rig arrives home here next week so I take some pics then.

one of the better set ups GM offered back then. guys that 4 wheel use the 14 bolt and change the front for a Dana 44. for street use and mild 4x4 in the brush you will not have any issues. very solid drive line..

Thanks LtEng5. This will see the local trails and will be our primary "road trip" Suburban. 235/85R16s will be the only size tire I will be running on her. She will get a 4 inch lift (National Spring) and a Banks Sidewinder turbo kit. Thats about it. I wasnt sure if the Corporate 10 bolt was a good axle or not. My next Sub will get a reverse cut Dana 60 up front and the FF14 bolt in the rear. Thanks for the info.

The corparate 10 bolts will take more abuse than a 44. We ran 10 bolts in both ends of are mud truck with a 700+ hp small block, turbo 350 with a trans break and cut 38.5 boggers on all 4 corners and the only thing we ever broke were axles in the rear. Replaced them with stronger aftermarket peices and never any more problems Your 6.2 won't make enough power even with a turbo to hurt your frontend.

You should have the 10.5 14 bolt I think. It is a full floater and a great axle. The 10 bolt up front is just as strong as a 44. They are basically the same axle. It can be upgraded with stronger parts if needed. I would wait and see with that. The turbo 400 is also good, will take anything you can throw at it. The np 208 is not the greatest. I prefer the np 205 for strength. But the 208 has a lower gear ratio in low range. All in all you have a decent truck. Other than a sub is too long for any decent wheeling

That 208 t-case ain't no slouch, thats what was in the truck mentioned above and we never hurt it. To tell you how tuff they are, we left the line at 5500 rpm on the trans brake and when you release the button thats the first thing that gets hammered, they are tougher than people give them credit for thats for sure.

That 208 t-case ain't no slouch, thats what was in the truck mentioned above and we never hurt it. To tell you how tuff they are, we left the line at 5500 rpm on the trans brake and when you release the button thats the first thing that gets hammered, they are tougher than people give them credit for thats for sure.


That is true, but a 205 is still stronger. Really the 208 and 203 got a bad wrap just for being chain drive. It was new technology that had peeps scared. The hot rock set up is a hybrid 205/208. That puts the 208 planetary piggy backed onto the 205. You get some low low range and the strength of the all gear 205.

Thanks guys. I am happy with the purchase so far. It will be here Thursday. I believe mine has the 9.5 ring geared Corporate 14. For some reason I thought the mid 80 Subs had NP205. Not sure what I was thinking but again the NP208 is a good unit as well and will serve just fine with stock size tires and light trail service. I live in Nevada and although we can get some nasty trails most I travel on with the family are somewhat tame. The draw to me for the Sub was the length and ability to carry my family. Then with a little finageling I can adapt a vehicle tent off the back end (rear doors open) and we would have a small house worth of space to sleep in ect ect. My other Sub will be more Expedition orientated and will outfitted so. I also plan on getting M1009 (Blazer) and build it out also with a dana 60 front Np205/203 and Corporate 14 bolt rear. But for now I will be building this sub for highway service and school bus for the wife.

here is a pic of my old Suburban, still kinda miss her!

Hey! Thats a nice Burban!

I loved my 208 because of the way the low range gave me a nice set of gears that were just below and above the high range 1st gear ratio of my SM465.

I didn't like it so much when the front half of the case broke under load.

I also liked taking it out by myself becuase it didn't weigh 200lbs....