4Wheel Drive Binding

[keith.wilson]

I've got an 87 4Runner with a 5 speed tranny. When I put into 4wd I can only go about 3 or 4 feet and it binds up to a stop. They guy I bought it from said it just needs new hubs..... It doesn't have any grinding and drives fine in 2w high. Anyone have any suggestions before I start buying part after part trying to figure it out?

I'm hoping it's not the T-Case. Or could it be the CV joints????

[KLF]

The hubs won't have anything to do with this. Nor will the CV shafts. Doubtful that it's in the transfer case.

Are you sure both axles have the same gear ratio?

Are all your tires the same exact size?

You're not doing this on pavement are you?

[Hilux]

Originally Posted by KLF

You're not doing this on pavement are you?

DAnag! beat me to it! :fingersnap:


or the ratios are different.

[missouriman]

you have two different gear ratios. most likely stock in front and lower in the rear end.

[Hilux]

My 91 acted just like that when I bought it. Turns out because the TC does not allow for over under drive like an AWD would. It would load up and not allow me to go from H4 to H2 at all, till I backed up and pushed up on the lever at the same time to release the bind. So that when it briefly un-loaded it would hit H2, other wise, no way in ell it would....no matter how hard I tried. It once hung up real close to my house and since I was where I shouldn't have been...I drove it in 4WD to the house. Thats when the front end started binding real bad and it dawned on me why.

No PT TC should ever be engaged while on a hard surface. It must be on a surface that will allow for slippage when it starts to wind up. And since its so minimal and most often our stuff is "off-road" to begin with, thats why we don't feel the wheels slipping form gear bind.

[missouriman]

jack it up... lets say do the front first. have friends turn both tires at the same speed and measure the revolutions of the drive shaft. use a tie wrap on the drive shaft. put it strait up then have your friends turn the tires. you can also use a piece of card board or something like that and count and mark where the tie wrap stops.
Now go to the rear and do the same thing.

so 4 revolutions and past 12 to 1 o'clock is a 4.10 ratio.

5 turns and 3 o'clock is a 5.29 ratio.

4.10


4.56
4 turns and just past 6.
4.88
5.29
5.71
those are the only ratios that I am aware of for toyota.

4.88 four turns
and 10 o clock.

I hope that makes sence.

do you feel the front plowing or the rear dragging?

or wet grass and put it in low 1st and get out and take a look as it idles forward.

[2ndGenToyotaFan]

yup, different ratios... I'd bet my last dollar on it. There are a few links in the FAQ thread, under the general info section I think... about finding your differential ratios.

[beatdown83fj60]

Maybe a grenaded ring and pinion in the front? I would get on soft ground and lock the hubs in and try to drive it in 2wd to see if there is anybinding going on up front with just locked hubs. It'll become obvious very fast.

[Hilux]

Originally Posted by beatdown83fj60

Maybe a grenaded ring and pinion in the front? I would get on soft ground and lock the hubs in and try to drive it in 2wd to see if there is anybinding going on up front with just locked hubs. It'll become obvious very fast.

locking the hubs, one or the other, then turning the front DS (TC in 2H) will have the same results. Only you won't have the motor x tranny to power through what you can't feel, and possibly break or finish off what damage there could be already.


Do the 4WD field test:

To determine TC. Place in H4/L4 and try to turn the front DS. Front hubs are un-locked.

To determine front diff, lock both hubs then try to turn DS, then to check either side, unlock one side, turn DS, then relock and repeat for the other side. TC is un-locked or in 2H.

You can also determine if its got a locker or limited slip this way

And you should also be able to determine the gear ratio this way.
Only in place of the tire rotating, it would be the half shafts.

[TrickyToy]

Some thing is messed up for sure, sounds to me like different ratios too.
You should "play" with it on a dirt type of surface......BUT a normal working 4wd will not bind to a stop on a hard surface. You will get some binding when turning on pavement.
I just bought an 87 runner on Saturday and tried out 4H and 4L on my paved driveway. Both worked fine with no binding, my driveway is about 50 yards long.

[Hilux]

Originally Posted by TrickyToy

BUT a normal working 4wd will not bind to a stop on a hard surface.

Mine wanted to, but I powered through it. (in the above instance)


Unless the tires are exactly the same dia, and the TC does not allow for over run/ under run, I don't see how, "a normal working 4wd will not bind to a stop on a hard surface".


ALL the part time 4WDs I've been in, I could feel the steering fighting on hard surfaces.

[TrickyToy]

Every 4wd I've owned over the years have been driven in 4wd on hard roads at one time or another and I never had any problems.
Well almost, I used to have a 1977 Dodge Power Wagon that I used mostly for plowing, I now use a 78 Ford. Both of these trucks are stick and 1st gear is a creeper. With both of these if I try to turn sharp from a dead stop in 4wd on dry pavement they bind up.

[Hilux]

I meant every GEAR DRIVEN TC'd 4WD

[theo]

Originally Posted by Hilux

and the TC does not allow for over run/ under run

I can't get my head around this one. I've never had a problem going in a straight line on pavement with any my 4x4s, as long as the tires are all the same. And as expected, lots of binding on turns.

How does a TC allow over/under run? Just curious is all.
theo

[Hilux]

Originally Posted by theo

How does a TC allow over/under run? Just curious is all.
theo

haha, you asked

The chain in a chain drive can stretch.

And the center diff in some AWD cases can accommodate for differentiation

[missouriman]

you guys make it sound like you have never driven your trucks, locked in 4 wheel drive, on a hard surface.

I do all the time in four wheel drive. rock crawling, I turn sharp also.
I doesn't bind to a stop.
hard packed dirt, rough flat rocks.

just going straight it should not bind up.

[Man Jerk]

Originally Posted by missouriman

just going straight it should. not bind up.

x2.

[WarDamnEagle]

My money is on the different ratios. There is no way that it would bind to a stop in "3 or 4 feet" just because you put it into 4H on asphalt or concrete if the ratios and tires were the same.