Need help with front end head-scratcher

[jembourbe]

Normally, I just ignore comments like these, but you're wrong. The FJ40 is fulltime four wheel drive. The transfer case only has a high/low selector lever, meaning both axles drive the vehicle. Always.

No. An fzj80? Yes, but not an FJ40

Back to the op: any chance there's a broken locker in the front diff? Just a thought

 

[jembourbe]

 

[pb4ugo]

All time 4wd vehicles have a differential in the tcase just like in an open diff. It has to. The tcase diff can be locked to apply equal power to the frt and rear end. The FJ40 does not have this provision. In a 40 , when the tcase is shifted to 4wd power is equally applied frt and rear. When the 40 tcase is in 2wd with the hubs locked, the gears in the frt end are being pushed by the rotation of the frt tires. There is no power being supplied from the tcase.

 

[pb4ugo]

As to the OP, from what you describe the issue is most likely in the wheel bearings, hubs or brakes. I doubt it's internally with the diff.

 

[Malleus]

Congratulations. You have a selectable transfer case. Not everyone does. And that still has no bearing on the lockout hubs disengaging the transfer case. Your transfer case front drive can only be disengaged via the transfer shift lever, not the lockout hubs, which was the point of my original post.

 

[squeezer]

Kurt, maybe you have a different transfer case in mind than mine. My '77 only has high and low, not front and rear. My '76 and '80 also only had Hi/Lo, IIRC.

Malleus,

Can you post a pic of the front drive output on you Cruiser.

What you have described does not line up with any Pre 80 series I ( And likely anybody else here) has ever seen.

 

[jim land]

I think you don't understand @Malleus
To get no load on the front diff, you need locking hubs on free position and 2h on the t-case , nothing will move .
Almost all 40 are part time with 2h position in NA

 

[Malleus]

Yes, I understand very well that if a selectable transfer case is set so that the front drive is disengaged, and if it has locking hubs which are locked open, there will be no load on the gearset. That wasn't the point of the OP's question, nor my observation.

Locking hubs have absolutely no effect on the transfer case, not the front differential carrier operation. They only lock the front driveshafts to the wheels. Nothing more. If the transfer front drive is engaged and the locking hubs are unlocked, the front drive still turns every time the rear does. The fact that there is no load on the gearset is irrelevant. It still turns.

I accept there will always be someone who believes that locking hubs have some magic value, but it's simply untrue. You can't reason someone out of a belief they haven't reasoned themselves into.

When I worked for Dana we studied these extensively, because the floor personnel were certain that they could get paid bonuses for suggesting design changes which would modify the ag/industrial off-highway axles to resemble their jacked up pickups. The program required us to refute the claims so that they would stop submitting these frivolous suggestions. No evidence was ever found linking improved performance, in any measurable way, to locking hubs.

 

[cruiseroutfit]

Normally, I just ignore comments like these, but you're wrong. The FJ40 is fulltime four wheel drive. The transfer case only has a high/low selector lever, meaning both axles drive the vehicle. Always.

The only way an FJ40 is not fulltime four wheel drive is when the front axles are fitted with locking hubs, removing the left and right driveshafts from engagement. To my knowledge, North American FJ40 front axles were fitted with lockout hubs as a dealer installed option.

You can argue, as many people have over the last several decades since locking hubs became commercially available, that they have benefits. The only real benefit locking hubs have is profit for the manufacturers supplying them. The ring and pinion in the front axle turn regardless of whether the driveshafts in the axles are connected to the wheels or not. The argument that there is no load on them since they are not connected to the wheels, and therefore do not wear, is wrong. The ring and pinion gearset is hardened to prevent wear and strengthen the overall gearset. Normal driving loads present no more wear on the front gearset than on the rear gearset.

As to increased mileage, I've never seen proof of that.

Well, I'm glad you didn't ignore my wrong comment

Post a pic of your dash/shifter or better yet your actual t-case. If you truly have a full-time 4wd 4x Series transfer-case, it's absolutely the rare exception, not the rule. And if that is the case, I would love to see it! I've seen the 2wd 4x Series t-case but never a full-time. What is it using to balance front-to-rear? A center-diff? A viscous-coupler? Educate us!

The rest of your comment isn't worth disputing as it's both inaccurate and misleading. Toyota offered free-wheel hubs from the factory starting in the 70's and they were standard from the factory for many markets by the early 80's and continue as a factory option on part-time 4wd variants to this day. Additionally port/dealer installed hubs and end users hubs were extremely common and are to this day for a reason.

I've never claimed it's a performance upgrade, but for longevity of parts it's an absolute no-brainer. Additionally vibration and noise, particularly noticeable in old ball/claw Cruisers or those lifted. Run 70 mph with hubs locked down the highway in an old Land Cruiser, you'll generally know the front-end is NOW spinning

I've spent time in and around 1000+ 4x Series around the globe and from around the glove over the past ~30 years. We have numerous 40, 41, 42, 43, 44, 45, 46 & 47 Series models in the collection at the Land Cruiser Heritage Museum that I regularly spend a great deal of time around. All part-time t-cases, some with drive flanges and others with free-wheel hubs. I stock new 4x/6x/7x OEM Toyota t-cases, stock and build used t-cases, etc... all part-time. We also stock 8x/450/100/470 t-cases in their full-time HF2A variant. I'm quite familiar with Land Cruisers and their t-cases.

I kinda have a thing for the history of many things Toyota including hubs

The common 4x Series PART-time tcase fwiw

 

[cruiseroutfit]

Kurt, maybe you have a different transfer case in mind than mine. My '77 only has high and low, not front and rear. My '76 and '80 also only had Hi/Lo, IIRC.

Post a pic of yours!

 

[pb4ugo]

A broken birfield or in American lingo a broken axle joint is a good reason to run lock out hubs and have a 2wd option.

 

[peesalot]

Malleus, regarding the FJ40 being full time, you are wrong, period.

 

[cruiseroutfit]

There’s no FD engagement lever on the later 40’s?

Yes, there is a FD engagement on nearly all 4x Series, early, mid, late, etc. Some examples:

Early vacuum operated on the dash:

The typical ‘L’ pattern H2-H4-N-L4 mechanical case:

or the later version found in the 4x with fully mechanical Tcase shifting

The late model 4x w/vacuum operated FD:

Dash switch for H4

And floor shift for H2 to L4

 

[jim land]

I just love the "magic" of my locking hub , it keep the shafts from turning .

 

[cruiseroutfit]

I just love the "magic" of my locking hub , it keep the shafts from turning .

Allegedly

 

[onemanarmy]

Yes, I understand very well that if a selectable transfer case is set so that the front drive is disengaged, and if it has locking hubs which are locked open, there will be no load on the gearset. That wasn't the point of the OP's question, nor my observation.

Locking hubs have absolutely no effect on the transfer case, not the front differential carrier operation. They only lock the front driveshafts to the wheels. Nothing more. If the transfer front drive is engaged and the locking hubs are unlocked, the front drive still turns every time the rear does. The fact that there is no load on the gearset is irrelevant. It still turns.

I accept there will always be someone who believes that locking hubs have some magic value, but it's simply untrue. You can't reason someone out of a belief they haven't reasoned themselves into.

When I worked for Dana we studied these extensively, because the floor personnel were certain that they could get paid bonuses for suggesting design changes which would modify the ag/industrial off-highway axles to resemble their jacked up pickups. The program required us to refute the claims so that they would stop submitting these frivolous suggestions. No evidence was ever found linking improved performance, in any measurable way, to locking hubs.

Wut?

In NA spec 40/55/60s, the front shaft does not spin in 2wd with hubs unlocked

 

[Living in the Past]

Fj40 are not full time 4wd , the locking hubs are usefull for less wear on parts and better mpg

Not quite all are part time 4WD. A few full time 4WD made it to the US in the mid seventies. These were prototypes. There are some survivors.

Yes, there is a FD engagement on nearly all 4x Series, early, mid, late, etc. Some examples:

Early vacuum operated on the dash:
View attachment 3510050

The typical ‘L’ pattern H2-H4-N-L4 mechanical case:
View attachment 3510057
or the later version found in the 4x with fully mechanical Tcase shifting
View attachment 3510064


The late model 4x w/vacuum operated FD:

Dash switch for H4
View attachment 3510062
And floor shift for H2 to L4
View attachment 3510060

Don't forget this one.

 

[cruiseroutfit]

Not quite all are part time 4WD. A few full time 4WD made it to the US in the mid seventies. These were prototypes. There are some survivors.

CDan mentioned to these same prototype units. I've never seen one and only heard the same anecdotal stories about them. As they were prototypes and not production units, there would be no EPC evidence of them. Have any photos by chance? I did a quick search here on Mud and couldn't find anything more than discussion. @orangefj45, have you ever seen a factory full-time 4WD 4x Series t-case?

I guess if we delve into the prototype variants that did or could exist the history of Cruisers is very different. I've seen some random stuff around the globe that was purportedly a Toyota prototype, some obviously are not, others could be? Toyota doesn't offer a ton of info about their prototypes to this day.

 

[cruiseroutfit]

Back to the OP. I'm working through the symptoms here.

When moving (20-30mph): Rattling and thumping from front end. No vibration or pull on steering wheel, no loose steering, no strange smell. Intermittent high-pitched whining sound.

That does sound like the potential symptoms of hubs engaged and back-spinning a slippy front driveline or a single locked or stuck hub spinning a broken birf? Though it could also be brake related.

Wheels locked up when moving and stopped:

That could still be something in the birf (broken birf binding) or diff (check of gear catching on ring/pinion) BUT if you can confirm the hubs are not only unlocked but actually working, then it simply has to be wheel bearing or brake related.

 

[jim land]

No locking hub at dana jewelry , just locking ring