per5uas1an

Hi Im new to the wheeling scene and I just picked up an 85 yota pickup 4x4 SAS. I was wondering about when I engage 4 wheel drive and lock my manual front hubs. Does that means that the front wheels are locked together? But separate from the rear wheels that are open diff. And that if i were to get uneven traction the rear wheels will get no traction.

Now if I got a locker for the rear axle. Those two wheels will now be locked, right?

Hopefully someone understands what Im trying to say. I have so many questions in my head and just dont know how to get them all out in order. It would be great if someone can just give me details as to how my 4wd truck transfers power to the wheels while managing uneven traction conditions. The truck is all stock. Also would a rear locker be a good idea? What kind?Why? Thanks http://img404.imageshack.us/img404/5240/p1010146nc2.jpg

Kaleb

First your truck is not SAS'd. It came factory with a solid front axle.

When you engage 4 wheel drive the transfer case delivers equal power to your front and rear differentials. If one tire loses traction on either the front or real axle the opposite tire on that axle will get the most if not all of the power. If you installed a locker in your rear differential this will prevent one tire fire by giving both wheels equal power. Same goes for the front differential.

Read this to understand how differentials work.
http://auto.howstuffworks.com/differential2.htm

Read this to understand how locking differentials(lockers) work.
http://auto.howstuffworks.com/differential6.htm

per5uas1an

Hey, Thanks for the info. It was a great help. Now in your opinion what type of setup should someone use if they are planning to do some mild wheeling and mudding. Is my setup efficient or should I get a locker of some sort for either the front or rear?

Kaleb

Try looking into a lockright, or aussie locker. If you are handy with tools you can most likely install it yourself. These lockers are a good bang for the buck, and will most likely be the best upgrade you get for your truck.

ewong

just be aware that auto lockers (lock rite or lunchbox lockers and Detroit (replaces the carrier)) have some particular effects on the STREET.

These effects may or may not be an issue for you and your driving technique and daily use.

XtraSlow_XtraCab

Hey there per5uas1an! I have an 84 that is basically stock except for 2" of lift (and those springs are sagging now anyway) and 31" tires.

When it comes to mud, lockers won't really help anyway. I mean... I guess they would a LITTLE. But, what good does it have both tires spinning, if neither can gain traction anyway? Mud is pretty tricky stuff and anyone that's said they've never gotten stuck is either lying or not mudding enough. I'd have to say, that MY problem in the mud, is tire type. I have great tread, but it still gets clogged up and acts bald with all of the mud that builds up inside of the tread. (and my 31" don't handle ruts very well)

I generally only get stuck in mud crossing through water-filled areas and trying to recover. (If you go fast enough through it, you're generally OK). And ruts... ruts are bad

Lockers are mainly great for dry rock crawling, etc. You did however mention MILD offroading. I take this as 'you can't afford to break anything because its your daily driver'. I know atleast, that's the boat I'M in. And what I consider mild, doesn't really call for lockers. Then again, I don't rock crawl. I just do "trail riding", crossing creeks and small rivers, and mudding. Because, this is also my driving-to-college truck.

In all honesty, I've never owned a truck with lockers. All one-legger diffs. BUT, I seriously doubt that lockers would help in mud. If you're samrt about where in mud you go, and how to approach it, lockers aren't a necessity.

drew303

With front and rear open difs power will always transfer to the tires will least resistance.

The front and rear axles get equal power distributed to them. If you lock the rear with the front still open the front tire with least resistance will only spin as fast as the rears and vice versa with a front locker, rear open... lock both and all the tires will spin at the same speed, generally the same speed as the one tire with MOST resistance...

thats a pretty dumbed down explanation.

In an AWD car theres a viscous clutch that distributes power front and rear variably which is why All wheel drive vehicles are different from transfercase type 4x4 vehicles. AWD essentially eliminates most of the binding and gear fighting associated with 4 wheel drive (Transfercase) by allowing all 4 tires rotational speeds to vary easier.

Kinda why manufactures sticker warnings not to drive 4x4's over 30mph generally. AWD like the subarus can go very fast =p

anyhoo, lil offtopic there but worth mentioning.


Lockers actually do help in mud but make traversing hillsides difficult and more dangerous. With open difs in flat n level mud power is sent to the tire thats going to find the least resistance..with a locker equal potential for traction is gauarenteed on both tires.. instead of leaving the tire with traction without power to utilize it.

drew303

kinda elaborate on my last paragraph there

you take off from a dead stop on a muddy road. With an open differential one tire will break free before the other and all the power will transfer to it while the other only rolls with the forward movement of the truck..

A locker prevents power from singling out one tire. both tires will break free at the same moment and you're gaurenteed to utilize twice as much traction as an open differential in that sort of situation.

many sports cars come with Limited Slip differentials for that very reason .. I actually think the celica came with a factory LSD, tho i think it was a factory option, not standard.

linuxrunner

XtraSlow_XtraCab,
I have found that lockers help a great deal in the mud, more so than any other type of wheeling i do.

Lockers on a DD is something i would personally shy away from tho, unless it is selectable.