Confused. I have front GT4 option. Np1, 2hi,4hi,4low dash switch. I was searching car-part.com for front diff,and it brings up choice of with, without ZR2 option. How can I tell if I have ZR2 option. Do not have ZR2 truck. 1999 S10 Blazer LS 2 door auto 4.3L
I contacted GM online but it is vintage and there is a fee to find out if I have ZR2 option.I am confused did not know could have ZR2 option on non ZR2 Blazer.

Anybody Help.

Thanks.

 

Check the RPO codes on the sticker in the glovebox. If you see ZR2 on there, then you have that package. The ZR2's and a few 2DR 5spd blazers have an iron front diff that's much stronger than the regular 4WD trucks. That could be why you're seeing a different differential for the ZR2...

 

There would be some other visual cues as to whether you have a ZR2 as well, but the RPO code list is an easy place for verification (provided the glove box door wasn't replaced).

 

ZR2's did not come with an iron front diff, only those with the np233 transfer case and the five speed manual transmission. I only wish they all had the iron front diff!

 

No ZR2 on sticker. One more question. I was looking at new Cardone cv half shafts.Rock Auto has some (one of few places that I can find that ships to Canada) but it only lists non ZR2 or with ZR2. All Data lists part numbers 937 20063 right, 260 55052 left then it says order by gear ratio. Are all the half shaftaxles different for each gear ratio or can I go with the non ZR2 half shafts and not worry about gear ratio?

I talked to the guy at Rock Auto buthe sort ofcould notsay for sure. He said the axles he has are for 1999 S10BLazer 4.3L.

Thanks foragain for help.


SCRATCH THIS POST.I THINK THE ABOVE PART NUMBERS ARE CORRECT, ORDER BY GEAR RATIOWASREFERING TOFULL TIME I THINK. SOI SHOULD BE ABLE TO ORDER NON ZR2 OPTION AXLES.

NEED TO MAKE CORRECTION. ALL DATA IS KIND OF CONFUSEING. ORDER BY GEAR RATIO MIGHT BE REFERING TO AXLE SHAFT ONLY.

THANKS