well i checked on zr2 axle | eBay and there are quite a few axles that say they're for a zr2, but they only have them for a 1998 blazer at the latest, any possible fitment issues?

how about one of these? looks like it would be perfect GM 7.5 7.625 10 BOLT POSI 28 SPLINE 3 SER AUBURN GEAR CAMARO FIREBIRD S10 BLAZER | eBay

 

I don't know much about those axles from eBay, although the last one you posted appears to be what your looking for. Someone else can probably answer that question better.

As for determining what gear ratio you have, Kyle posted a link in the Tech Article section to a VIN decoder that will tell you everything in your truck from factory. The most common gear ratio's for regular Blazers are 3.42 (RPO GU6) and for ZR2s is 3.73 (RPO GT4). I replaced my rear axle and front diff with ones from a ZR2 to get the lower gears and G80 locking diff. Its a bit of work but if you have the time and inclination its definately doable. For me it was worth the effort.

 

I never said it was "just" driving style, only that it's a big factor.

 

Isn't the ZR2 axle a few inches wider than a regular Blazer? I know that would be an issue here in MA with inspections, due to the tires coming out of the wheel well. They'll fail you for less than that here ...

 

FIRST before you go swapping axles and tires, you need to make sure your 4x4 is working properly. Make sure the t-case is engaging and the front axle is locking. It's not uncommon to find that there's a bad vacuum line to the t-case actuator, meaning the front axle isn't locking properly.

I've found that my Jimmy is pretty good at getting through some rough stuff. Like things you wouldn't think it could get through. Even with an open rear.

 

the rear tires seem to be pretty well inside the fenderwell, so even if it is a bit wider i think i'll be alright

any test i could do to check this? i already tried getting barely any weight on 2 diagonal tires, but it didnt give me a good result

 

Take a buddy with you onto a dirt road. Have him stay outside the truck while you toss it in four wheel and mash the gas. If the front tires spin, your 4 wheel works.

 

Get the front end in the air, run the truck for a few minutes, shut it off, turn the key on but DON'T start it, throw it in 4x4, then try to spin either front wheel. Should be tough to spin one of the wheels, especially with the rears on the ground. Then try to spin the front driveshaft if the wheel test doesn't tell you anything (sometimes they both will turn due to the open diff). In 2wd it should release the driveshaft & spin freely. If it spins freely in 4x4, you either have a vacuum leak, a leaky actuator, or a bad t-case vacuum switch.

TheRandom1's test is quicker though.

 

personally i think the best option would be to go to the junk yard and look in the glove boxes of all the blazers and look for the same ratio code you have and for the G80 code.
here are the codes and what they mean.
g80 is locker
Gu6 is 3.42
Gt4 is 3.73
Gt5 is 4.10

personally i guess i got lucky and i have the the Gt4 G80 in my 4dr blazer.

 

so if i just pin it on say wet grass and if one of the front wheels spin then im good, but if neither of them do then my 4wd doesn't work? and btw, how do you like your flowmaster super 40? i've been looking at picking one up