I either have problems or I'm an idiot. Transmission and 4WD. Answer: I'm an idiot.

[Frkens]

Hey everyone,

So I was on the beach trying to surf the other day. Got stuck in the sand. I did not have 4WD engaged, but the right rear wheel still kept taking all the power though. The only wheel that moved was that one. I had the differential lock engaged in the front, but no 4WD. Am I misunderstanding something completely or do I have an electrical failure? Or something third?

The other thing is... When I do +2500 revs on the highway for 20-30 minutes I get a warning light, that my ATF is hot. So I pull over, let it run till the light disappears, then I stop the engine for 20 minutes and drive again. Now if I keep it at 2000 revs it can go for a really long time with no warning lights. I had the transmission checked at a professional 5000 miles ago, and had replaced ATF, filter, magnets, gaskets. No trace of small metal parts in the fluid. The ATF level is a little high. Could that be the problem?

What do you say, am I an idiot?

 

[PortFJ62]

Your vacuum solenoid might be out that engage the t-case. There should be a red and blue one near the firewall on the pass side. With the 4x4 gauge off swap the hoses on the solenoids then hit the button and see if that engages the t-case. If so crawl out then reverse them again for normal drive.

You might need a tranny cooler to keep your temps down..... Worked for me back in the day.

 

[mwebfj60]

FJ62? When you say you had the front diff lock engaged are you saying you had the hubs locked, 4wd button pushed, or shifter to low or do you have a diff lock?
Pushing the 4wd button or putting into low sends voltage to the 4wd solenoid in engine bay. That solenoid then passes vacuum to the vacuum shift solenoid to move the fork to engage the gears in the transfer case.
How overfilled is the trans?

 

[Frkens]

@PortFJ62 thanks a lot for the fast response! Stupid question, but how do I see if the t-case is engaged? I do have a tranny cooler already and I also had that checked along with all connections 5k miles ago.

@mwebfj60 thanks for the response! Fj62 yes! I had the hubs locked and the button off and the shifter in 2wd. I thought the locking hubs was the same as differential lock. It is overfilled by half an inch on the measuring stick which is what I suppose is half a litre.

 

[mwebfj60]

You’ll either have to push the button or shift the lever to Low to engage the transfer. You can leave the hubs unlocked and push the button, then get underneath and see if you can turn the front driveshaft by hand. Once you push the button or shift into low without the hubs locked you shouldn’t be able to turn it. Once you turn the button off and/or shift back to 2wd with hubs unlocked, it should turn by hand.

Sounds like maybe your torque converter isn’t locking up in OD. There are some tests in the FSM to check the TC. I would pull the trans drain plug and get that 1/2 Litre out of there and get the fluid level right.

 

[OSS]

It's not clear whether you have locking differentials front & rear or not (not the same as locking hubs)

If you don't have a locking rear differential, only one rear wheel will spin when you lose traction. If you do have a locker, then it's not locking. It's best to air down the tires for soft sand to ~ 12-15 psi (I prefer 12 and go slow) and engage 4WD before rolling out on to the sand. Once you dig in, it's a lot harder to get out. The goal is to never start spinning the wheels. Digging a grave.

 

[Frkens]

Problem solved: I am an idiot for a couple of reasons.

1. I always thought my FJ62 was front wheel drive when in H2. It's not. It is rearwheel driven and 4WD is never engaged until the locking hubs are engaged. This is how dumb you look when you assume stuff which I did... All in all it makes sense why the front wheels were not spinning and the right rear wheel took all the power. Discovering this I wonder why you would ever make a 4x4 without diff. lockers. Doesn't make a lot of sense to me.
2. I thought that locking hubs were the same as differential lockers... -"-
3. My car is a California vehicle and does not have differential lockers (I read that's because it's from California). I looked for the cable lockers for a long time after I saw them in the manual. With this reason it makes sense why I never saw the..

I am taking the car back home to Denmark with me after my overlanding trip across the Americas. And then I want differential lockers! Is it possible to install them aftermarket?

 

[stevebradford]

Yes you want them! I love mine. You can only install cable lockers if you have a full floating rear axle and find them...

Full float info/parts however there are lots of other axle locker options that will work with your semi floating rear axle.

 

[SteveH]

You might consider finding and reading, cover-to-cover, the owner's manual for your particular truck. Since it's US-spec, there are used owners manuals floating around on eBay and Mud.

 

[2mbb]

4x4 and “part time 4WD” are somewhat confusing terms. When in 2WD you will get power to one rear wheel. When in 4WD (with hubs locked) you will get power to one rear wheel and one front wheel. So 4WD is better than 2WD.

You need to add a locking differential to the rear and/or front to get power to the other wheel(s). Of course this is only used when extreme traction is needed.

All wheel drive (AWD) uses a third differential to allow only one wheel (front or rear) to get power. But nowadays there is automatic traction control that gets the power to the wheel(s) that need it.

 

[PortFJ62]

Problem solved: I am an idiot for a couple of reasons.

1. I always thought my FJ62 was front wheel drive when in H2. It's not. It is rearwheel driven and 4WD is never engaged until the locking hubs are engaged. This is how dumb you look when you assume stuff which I did... All in all it makes sense why the front wheels were not spinning and the right rear wheel took all the power. Discovering this I wonder why you would ever make a 4x4 without diff. lockers. Doesn't make a lot of sense to me.
2. I thought that locking hubs were the same as differential lockers... -"-
3. My car is a California vehicle and does not have differential lockers (I read that's because it's from California). I looked for the cable lockers for a long time after I saw them in the manual. With this reason it makes sense why I never saw the..

I am taking the car back home to Denmark with me after my overlanding trip across the Americas. And then I want differential lockers! Is it possible to install them aftermarket?

You are not an idiot and this forum is a good resource, but I'm glad you did not place this in Chat. They could have eaten you alive. That is a looney toon nut house arena.

 

[Frkens]

@SteveH that's probably the most embarrassing part. I had read through it pretty thoroughly. But considering this I guess it wouldn't hurt to do it all over again.

@2mbb Excuse me!? Four new heads just grew out of the monster you beheaded.
1) So actually 2WD=1WD and 4WD=2WD??
2) In this case then what is even the purpose of a differential? If power is only channeled to one wheel I'd say it's more of a gear than a differential. Or no? Wow'm more of an idiot than I ever expected haha... But this makes a lot of sense. It definitely explains why my FJ62 usually gets stuck in sand only on the right rear wheel.
Boy I am glad I asked so I only embarrassed myself to people I might never meet. Would be something different if I revealed my lacking knowledge towards the guys back home. They'd never forget.
So AWD is actually different from 4WD. Glad I got that figured out too.
3) When on highway with AWD, I guess it is then up to the manufacturers configuration which wheel is pulling. Or is there a rule of thumb? As for example 2WD?
4) My last question is then what about 4WD with locking hubs and no rear differential lock. In this case will I then be pulling on both front wheels and one rear wheel? I can't believe I'm asking this, but will it then be 3WD?? Hahaha I am having a good time imagining you guys reading this.

@PortFJ62 thanks for the encouragement, but I sure don't feel like an expert either haha.

Thanks for the help guys!

 

[SteveH]

1) - yes, with open diffs, you get one wheel at each end turning.
2) - Diffs allow you go around corners, where the outside wheel transcribes a long arc than the inside wheel. Try doing a u-turn in 4WD (hubs locked) if you wonder how well locked diffs would work on dry pavement.
3) - 'AWD' often connotes a center differential allowing interaxle differentiation to allow 4WD use on hard surfaces. FJ60/2s do not have this. Some AWD vehicles are primarily RWD or FWD, with the other axle being called on as needed. There are too many variations to describe here.
4) - All locking hubs do is allow the axles (still connected to an open diff) to connect to the driveshaft while moving. The diff is still open and you still have 1 wheel drive (to use your parlance) on the front axle.

Locking axles are not standard equipment for many reasons: tire life, drive train stress and wear, steering feel, safety (operator may use them under the wrong conditions), cost, complexity, reliability, etc. Also, 95% of 'off road' vehicles never see a condition where they'd really need it.

Tons of good, basic info here: How Four-Wheel Drive Works

 

[Frkens]

@SteveH thanks for the answers. So my FJ62 has open differentials? I don't understand why you would put that on a car like this? Thanks for taking the time to write this.

 

[Elbert]

US market models never had any of the OEM cool lockers or limited slip diffs that I'm aware of. Yes its good question why these are not installed at the factory..but they were not. Any 4wd used as a 4wd needs some type of traction aid beyond the transfer case.

 

[FJACS]

With respect to the ATF level. Make sure you are checking it using the correct procedure - The manual covers this.

If you are in fact overfilled. Disconnect a hose from the transmission cooler and start the truck, place it in gear and let it pump out a litre of fluid - it will either come out the hose or out of the cooler. Shut the truck down. Reconnect the hose - check and adjust the level until you get it correct.

 

[morganism]

OSS is right, you shouldn't roll out into sand without having a good compressor, dropping air pressure, and only stopping where you have a downhill or a fairly smooth place to turn around while still moving. Don't do 3 point turns out there. Also good to have a strong ratcheting strap to cinch down around a tire if you blow a bead, will give you a chance to reset a bead.

Leaving your rig to turn into a submarine, as you livestream it, is not a documentary, is a tragicomedy.

 

[2mbb]

I suppose on dry pavement driving straight with even tire pressure, etc. you will get power to both rear wheels in 2WD, but once one wheel starts spinning faster (if the 2F could even power a "burn out") all the power will go to that wheel. This is how a standard differential works. Newer vehicles with traction control work differently. For example brakes may be automatically applied to the wheel spinning fastest to divert the power to another wheel. True locking differentials will make both wheels on an axle spin at the same rate. Some automatic lockers (posi-traction) will lock the differential if one wheel gets spinning a certain amount faster than another.

Since the outside wheel spins faster than the inside and the fronts faster than the rears when cornering, some kind of differential is necessary for good road handing on dry pavement. Automatic lockers can act up when cornering. Locking differentials should be turned off (unlocked).

I think even in the 1980's the 60's series US market was targeting the early SUV crowd--It was a "station wagon" not a "jeep"...That's why we didn't get locker options, inclinometers, and other cool options. But I don't think the US FJ40 was offered with cable lockers either, so I don't know...

 

[Feistl]

To the op...

Jump on YouTube and have a look at some of the videos of "how a diff works", how "4wd works" etc.

There are some great videos explaining how and why diffs/4wd systems work and their limitations. Understanding these will help you learn to drive the 60 better.

Probably a good idea to watch some 4wd instructional videos as well.

 

[Frkens]

Hey everyone, thanks for the great response!

I am dreaming of upgrading my truck with locking differentials and a bunch of other stuff. I read that it's a good idea to find the OEM cable lockers, but that some people also take the E-lockers from the 80 series, or even buy a new air locker from ARB. Any pros/cons good suggestions for this newbie? And can I apply this to both front and rear, or would that not make sense?

@Elbert I agree, it would be nice. I almost can't believe it that my traction is that poor. Glad that I at least have 33"s.

@FJACS thanks, that's a good idea. I'll do that and send you a thanks in my thoughts today at whichever campsite we choose for the night!

@morganism I second you on that. I do have a compressor but a s***ty one. It takes around 30 minutes per tire. So I try to avoid sand as much as possible and don't air down till I get stuck... Which might could've been avoided if I had aired down in first case. Now if I make the dream build of this car, I will install ARB air lockers and install a compressor for them too. A compressor better and bigger so I in the future can lock my differentials, air down, inflate fast and drive in sand!

@2mbb I understand now. I thought that in fact only one wheel was powered with an open differential, but both of them do get power. However when one wheel starts spinning it gets all the power. Got it. I thought shortly there was open differentials, closed differentials and locking differentials. But closed is the same as locking. Check.

@Feistl good idea. I did so, and everything makes much more sense now. What confused me was that I misunderstood what was said about open differentials. Open differentials do only power one wheel on each axle when the car's stuck.