Hey everyone sorry this is going to be a bit of a long post.

At risk to sounding like a complete and utter newb, I need some 4x4 help. I have never owned a vehicle with 4WD. I've driven vehicles with 4WD but have never had to use it. I have a bunch of questions I was hoping you guys could answer for me.

How do you properly engage 4WD, do I need to put it in park first then shift to 4lo/ 4hi, then shift to drive?

When should I use 4lo and when should I use 4hi?

Is it safe to use 4WD on the highway/ freeway? What about on normal roads around town?

I've heard of "shift on the fly" where you can engage 4WD while driving. Is this possible with the 1st gen S-series?

Last winter, my girlfriend's mom was on her way to work and the main highways were closed due to snow. She took backroads, some of which are uphill. She drives a FWD Hyundai Accent... not the best for slick uphill snowy roads. My girlfriend and I were all the way in south Jersey in Cape May for my youngest brother's Coast Guard bootcamp graduation. My girlfriend's mom didn't have a cell phone at the time. Her work called us to tell us that she hadn't made it to work and was 5 hours late. We freaked out. We called all of the police stations in the area and found that there was a real bad accident on the highway, but of course couldn't tell us if she was involved or not. We were stuck in south Jersey as we wouldn't have been able to get home because the highway home in north Jersey was closed.

Three hours later we got a call that she had finally made it to work, just as her shift was ending. She had slid backwards off the road twice due to the snow. She had to wait for someone to come and push her out. All in all, a very stressful night. Now, she has a cell phone and I have a vehicle with 4WD... I just don't know how to properly use it... yet. Any help would be greatly appreciated. Sorry for the novel or a post. :/

 

You likely have the NV231 (manual lever on the floor) which is a shift on the fly transfer case. You can pull it into 4HI when necessary. It is never a good idea to drive in 4wd on high traction surfaces. It should be reserved for slippery conditions.

All that you have to do is pull it back into 4HI while driving. 4LO may take a bit of movement to get it to engage, but otherwise, you'll want to have the transmission in neutral or park to go in or out of 4LO.

 

and with 4LO, you'll only have a max speed of 40 to 50 KPH (25 to 30 MPH). 4LO is used more for crawling over big stuff, or for when pulling something really heavy out of a ditch.

the big issue with 4LO, that alot of people don't realize, is it almost triples the ratio for what the wheels require to turn. i think 2.73 is the standard (only?) ratio. this means that for the wheels to complete one full revolution, the trans will do 2.73 turns of the output shaft.

i've tried the 4LO in the auto trans Blazer/Jimmy's that i've owned, and have never really liked how it worked. now having a 5 spd (like in my '92 Jimmy) was much better for controling the shifts points-plus i didn't need to stop to put it back into HI range!

that's right, according to the Owner's Manual, in 5th gear & in LO range, you could just press in the clutch and jsut shift firmly & quickly, right into 4HI. couldn't belive it when i accidently found this in there (who the hell reads their manual anyways?), and was skeptical @ first. but after the first time, it was like, "that's it? sooooo easy".

sorry to stray of your OP a little, but i hop that helps you out a little more.

have fun this Winter, just don't get to cocky with it-hate to see anything happen to Jimma Jam.

cheers.

 

Yeah, I have the manual lever on the floor. Thanks for the help. I've heard that you can drive as fast as you want in 4-hi ...as long as you don't turn because that would be "bad." Any truth to that either way?

I don't plan on cruising around in 4wd, but we are supposed to get a lot of snow tomorrow night from what I have been hearing and my girlfriend, her brother, and their mom are like "hey, can you take us to work and pick us up?" I don't really plan on playing around in the snow, I don't have any lift and I don't know of anywhere I could off-road, except for Wharton, which is about a half hour from me (used to live in the next town over). Even then, I don't know anyone else with a 4x4 to go with.

 

The problem comes when you try to turn on high traction surfaces with 4wd engaged. The front driveshafts have to turn at the same speed or else they will bind. While turning, all 4 tires take a different path which means that the drivetrain will bind. On lower traction surfaces, one tire will just slip a bit and you will really not know. On high traction surfaces, you are asking to break something.

 

turning on dry land in 4wd will let you know not to do it again, i can say from experience lol. when i first got my blazer i was hesitant to touch the magic buttons cause i had no idea how any of that worked, when i finally did i thought i broke something cause i couldn't turn around for nothin in 4lo, and in 4hi, well, it was less than happy to be going to burger king.

the best thing to get a feel for it would be to find an open area to play with it and get a feel for it, mud can be like snow in that you really don't just stop all the time and it's much easier to get sideways. i went out on a back country highway and found a small abandoned something or other<really i have no idea what the hell it is> and it was enough of an area to play around and get a better idea of how everything works, even got a chance to figure how to get out of a mud hole on accident lol

 

So what if you're on a winding dirt road or icy snowy road? Can't use 4wd?

Sorry for all the questions... I just don't want to hurt the truck but I want to be able to properly use it if needed.

 

on loose dirt and snowy or otherwise slippery conditions you can use it as it will allow for the wheels to slip, on dry, paved roads the wheels generally do not, or at least not with out resistance.

i wish i had the link to how all that worked which i was reading earlier, i believe the site was 4x4abc.com, but basically what happens is, when you turn your inside wheels will spin slower, the outside wheels will spin faster as they have a larger area to cover than the inside. in 4wd all 4 wheels spin at the same rate, so when you try to turn on dry pavement your inside wheels do not slow down but rather go at the same speed as your outside, you can still turn just not tightly like making a sharp 90*+ turn, if that makes sense i know i'm not the most techy person

 

not sure if you've read all of the carnage i've inflicted on my Jimmy overthe years (it was alot!), but i've never broken a t-case or front diff-and i always drive in 4HI whenever there is any kind of weather falling on the ground.

be it rain, snow, a dirt road (so much more contol on the loose gravel-night & day difference), or even when exiting a parking lot (in Winter) to merge with traffic-the sand sittingalong the sides of roads from salting/sanding can be just as slippery as fresh snow.

you just need to remember that when you're driving around in a parking lot, out it back into 2HI-and not just right before you back into a parking spot. give it a few seconds to fully disengage before doing tight turning manouvers.

and you can engage 4HI @ any speed. i've engaged mine @ highway speeds whenever i've come across rain/snow, and have never had any issues in any of my 4WD trucks-it is a "shift on the fly" system remember. been shifting in and out like that since i've owned a 4x4 (?12? years now).

try not to be afraid of something you don't know/aren't framiliar with. learn all you can now, so that when the day comes when something does break, you'll at least be better prepared with the right questions to ask a mechanic.

 

Do the front hubs need to be locked on Blazers?