94 SR5 Mountaineer

Best vehicle in snow i've ever driven is my dad's '90 single cab 22re with wee little 225 walmart goodyears. With 4x4 and open diffs driving on ice covered roads it's never slid on me in 4x4.

UKrunner

So I'm getting a little confused. I understand about the locking 4wd and different diff speed front vs rear. I understand about open diffs. But what is this talk about locking hubs? Does my 4Runner have a locking front diff? Is that what the black things are sticking out of the center of the front wheels are for?

rattlewagon

YOu would know if you had manual hubs. All they do is lock the hub (wheel) to the cv shaft, your ADD doeas this for you.

Batman

i have a question that relates to this... im also pretty new to the 4wheel drive world... it was said a few posts back about being able to shift from 2hi to 4hi, and 4hi to 2hi while driving... does this hurt anything while doing so? and while leaving the front hubs locked, does that hurt anything as well, or is just the fuel mileage it hurts?

James Woods

iTrader: (1)

The decal on my dash from Toyota tells me
"H2-For on-the-road
H4-For off-the-road,sandy, SNOWY OR SLIPPERY ROAD
L4-For the maximum traction"

4Crawler

iTrader: (3)

No problem doing so. With front hubs locked, everything is synced up (front-rear) so you can shift 2H<->4H at most any time. Best to do so when moving straight ahead but not under heavy acceleration or engine braking or with tires spinning or making a sharp turn. When heading up to the mountains, I'll lock the front hubs before I get there and then can pop into 4H if needed.

sb5walker

4Crawler spoke to the 2H-4H shifting while moving being fine. As to leaving the hubs engaged, doing so does ding the gas mileage a bit, as you mentioned, since it causes the wheels to drive the front axles, differential and driveshaft continuously. The only problem I could see is possible wearing of the spindle bushings (or bearings, depending on year). The bushings in particular can get dry, and make noise. It's helpful to inject grease into them with a grease needle whenever you have the hubs off.

One spring I drove from Maniwaki Quebec to the middle of New York state before I discovered I still had the hubs engaged (in 2WD obviously), without any problems then or since (that was about 10 years ago). The hubs were engaged for almost all of the Quebec winter, tho I didn't do much driving.

Batman

alright, good to know