I am trying to figure out what type of 4 wheel drive my '91 4Runner has. I am assuming that it doesn't have locking (http://auto.howstuffworks.com/four-wheel-drive3.htm), since I can't see anything on the wheels. Depending on the system, does this mean it is really NOT a 4x4?

Just trying to get to now my 'runner a bit better...

Thanks!

 

Probably an open differential. You could jack up the rear & spin one of the wheels, if it's open, the opposing wheel will spin in the opposite direction of the one you are turning. Locked & some LSD's will spin in the same direction as the one you are turning. I have seen an LSD that spun like an open diff. maybe it was malfunctioning? I don't know.

 

Thanks.

I suppose that is the question. Does a '91 4Runner SR5 V6 come with a limited slip or a locking differential? Were those options at purchase time?

Thanks.

 

Hmmm, I do not know. I'm sure someone does know though, give the post time to attract the attention of some of the long term Toyota owners or hardcore enthusiasts; I'm sure they can tell you. Most manufacturers of off-road vehicles did offer options though, I'd find it odd if Toyota didn't.

 

Toyota offered a limited slip, but I don't think any made it into the US.

You have open diffs in the axles and a "locked" diff in the tcase, meaning your 4WD is actually 2WD (one in the front axle, one in the rear) at best. The power always goes to the "path of least resistance" so if you have a wheel off the ground (or even light) on each axle, you're not going anywhere.

 

Is this a "mod" project? Or is it just a "fact of life" that I will have to deal with?

Thanks for the info. I had a feeling it was a 2WD.

 

very well said. plain and simple. you're pretty much gonna have an open diff, unless the owner before you has done something that you do not know about. theres a sticky thread in "offroad tech" section about lockers and stuff like that. that might get you started.

 

just need to lock the rear.,. and it will get you ton and tons of places

 

TC didn't mean you have a 2WD, he meant your 4wd acts like a 2wd if you do not have lockers in your axles.

No 2nd gen 4Runner in the US ever came with Limited slip or locker options. All truck and 4runner t-cases in those years were part-time 4x4, meaning there was no "center diff" that allowed the front and rear driveline to spin opposite directions when traction was lost. Vehicles that do have a "center diff" (ie 2001+ 4runners, Highlanders, 91+ landcruisers etc etc) have a center diff lock option, where all that does is lock the front and rear driveline together in the transfer case.

You can install lockers in the front and rear diffs on your 91 4Runner, and gain "true" 4 wheel drive. But as it stands now, if you have two shifters in your 4runner, you have 4x4.

 

I call open differential 4x2 as most people do; not 4x4. You can have 4x4 if you lock it as others alluded to.

 

yea, but i didn't want to confuse the poor guy lol.

 

so do you call a 4x2 a 4x1?

 

Who are you asking?

 

go with an eaton electric push button locker than way is open when you want it and locked when you want it

 

Except that they Eaton doesn't make one for Toyota axles

 

Your truck is rear wheel drive with a part time 4x4 system that allows you to engage the front wheels in Hi or Low range. No limited slips or lockers were offered on you truck.

ARB, a popular 4x4 accessory company, sells what's called an air locker. Air pressure is used to lock the two wheels together . They run about $1200 installed roughly.

A cheaper option is to use a "lunchbox locker". They run from $200 for a Powertrax Lock Right (install at home- easy) to $600+ install for a Detroit locker.

Open diffs work well on fire roads and light offroading and are great on the street, but on more serious trails (deep mud or snow, rocks, climbing, you need a locker). Try it with open diffs for a while first before spending the cash on a locker.

 

do an arb in the rear and a auburn limited slip in the front

 

Except that Auburn doesn't make LSD's for Toyotas ...

dude - stop spreading misinformation

 

just through some aussies front and rear...that'll make it a true 4x4..lol..its what i plan on doing...rear first..then front..

 

auburn does make ls for toyota cause i have one and have had it for 5yrs.