Hey all, first post here..

I have a recently acquired 1999 Blazer with the infamous 4.3L Vortec motor, and the codes in the glove box says it has 3.42 gears. I'm looking to use this in sand on North Carolina's outer banks beaches. No digging, just getting on and off the beaches.

After owning a few Astro vans with the same 4.3L V6 and the same 3.42 gears I have found that a tire height of 26" is just about perfect for these motors to be able to make decent torque and do pretty well at highway speeds. 215x65 r15 are the best overall tire size for highway use, decent torque, good gas mileage, doesn't lose headway on a long hill.

It has the stock wheels now, with 235x75 r15 tires, 28.75" in height. Runs okay but is semi sluggish on the open road on any kind of a hill which is typical of this motor with highway gears and tall tires. Very hard to come up with M/S or All Terrain tires that are short, and the industry is pretty much moved away from making 15" tires anymore. Got any suggestions?

Likely will use different wheels when I get new tires for the sand, so a 16" or 17" wheel might be an option too.

How hard is it to change gears in these trucks? Would I be better off going to a 4.10 gear and using the taller tires?

 

The sky`s the limit when it comes to rear end ratios and tire sizes.Most G.M. rear ends are similar,they all share the same concept.When it comes to gear ratios..The higher you go,the more RPM `s you`ll have while driving on the freeway.Which means poor gas mileage.In your case it seems as it doesn`t matter about gas mileage.The 4.10 should work out for you,just make sure you always get a second opinion. Make sure you do your homework, don`t rush it.This isn`t a cheap task at all.Average price range to re work a rear end can range from $500-$1000.00.That`s just for labor.You want to do this one time that`s it.Take your time, make sure you know what you want.Then let her rip.If nothing goes wrong..The average joe who know`s what their doing should be able to do this task in one day.Good luck!

 

i run 373 gears and 33x14.00 tires on my s10 with the stock engine. not very good in 4hi but in 4 low it does great but you wont get much wheel spin out of it

 

The 3.73 rear ends are on most chevy mont ecarlo`s, grand nationals,It works well on the them while riding on 15 ' rims.But in your case you will have to step it up a notch.Higher the number, the smaller the gear would be.Which you will get more wheel spin out of it,more low end torque.I`ll give you an example the way they work.Like on a 10 speed bicycle, you put the gear on to the smaller sprocket, your able to peddle alot quicker with less effort.You slide the gear to the biggest sprocket, it`s harder to peddle with alot more effort to move forward.it doesn`t take a rocket scientist to figure this one out.You just have to make the right decision for your needs.