Best Driveway Test To Check 4WD Operation Is All Working OK?

[SherwoodNash]

Hey guys,

I had my SJ410 up on 4 jack stands recently when working on my fuel system.

Whilst lifted, I thought I'd check out the drive train and 4WD mode.

I started it up and put it in 4WD High and in 1st gear and checked operation. The rear wheels had full power, as well as the front nearside wheel, but the right front barely moved and I could stop easily by hand.

I thought I'd check the Aisin free wheel hub on the R/H side first. I removed the outer hub dial, fully cleaned/reassembled and put back on. The lock/unlock appears to be working OK (thanks WheeliePete!) https://www.youtube.com/watch?v=W78RkF1mUOE

Still no power to that F/R wheel, although other side is fine?

What are the next things you would check and in what order please?


Thanks!

[ScottieJ]

If you stop the wheel that is spinning did the other side start spinning? With open diffs the drive only goes to both wheels when the amount of traction is equal.

If in the air the drive would just go to the side of least resistance.

Sounds like it's fine to me.

[Jordi]

Its the way the diff works. Drive take the easiest route. If you stop the wheel that is turning the easiest the opposite wheel should turn better.

Could be as simple as the bearing on that wheel is slightly tighter or the brake pads binding ever so slightly.

Without diff locks you do not get even distribution of power to all wheels.

*edit* Scottie beat me to it but i had already written it

[SherwoodNash]

OK, great info lads

'Scuse the dumb questions, hopefully this post may be useful for someone else searching this issue at another time

I just jacked up the front only this time, engine off, handbrake off, and 4WD High and 1st gear selected.

With the Aisin hubs set on 'free', I was able to spin the nearside front wheel one whole revolution with one flick, on the drivers side front wheel, I only managed half a revolution,
just a bit more friction this side I guess from brake pads or bearing?

With the Aisin hubs set on 'lock' they each moved the opposing side in the opposite direction, I take it that's correct?

So just to clarify from my original post above, with the engine running in 4WD High and 1st gear, the fact that I was unable to slow or stop the nearside front wheel at all,
and the drivers side wheel I could stop with one finger, is all down to the diff selecting the easiest route, even if that's only due to a tiny amount of friction on one side?

If I repeated the full lift running test and chocked/restricted the nearside front wheel, would the drivers front wheel would become dominant and spin with full drive power then?

So everything is as it should be then?

[Jordi]

Pretty much.

[ScottieJ]

OK, great info lads

'Scuse the dumb questions, hopefully this post may be useful for someone else searching this issue at another time

I just jacked up the front only this time, engine off, handbrake off, and 4WD High and 1st gear selected.

With the Aisin hubs set on 'free', I was able to spin the nearside front wheel one whole revolution with one flick, on the drivers side front wheel, I only managed half a revolution,
just a bit more friction this side I guess from brake pads or bearing?

With the Aisin hubs set on 'lock' they each moved the opposing side in the opposite direction, I take it that's correct?

yeah that's what it's supposed to do

So just to clarify from my original post above, with the engine running in 4WD High and 1st gear, the fact that I was unable to slow or stop the nearside front wheel at all,
and the drivers side wheel I could stop with one finger, is all down to the diff selecting the easiest route, even if that's only due to a tiny amount of friction on one side?

If I repeated the full lift running test and chocked/restricted the nearside front wheel, would the drivers front wheel would become dominant and spin with full drive power then?

yes that is what would happen

So everything is as it should be then?

Sounds like everything is fine, well you might want to look into what's causing the resistance on the passenger side, could just be a sticky calliper that needs to be freed up

[ScottieJ]

Jordi beat me to it this time