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Old School 4WD

KMT15

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KMT15 Enthusiast

KMT15

Posted
Posted

Today at an intersection covered in slush/snow, I saw an old chevy truck spinning his tires trying to get up the hill, but he couldnt.  I could tell he had a locking rear end, but it do no good.  After about a min of spinning, I see him hope out and lock the hubs on both front wheels.  By locking both, does that mean he had a closed differential?  I loved being able to just push a button to get mine into 4wd

 

-KMT15

Kansas Kid Senior Enthusiast

Kansas Kid

Posted
Posted
I loved being able to just push a button to get mine into 4wd

Yeah, just wait until that POS push button quits working (And it will) and then see how much you like your 4wd setup.  I know that getting out in the cold to lock the hubs, and then having to yank on a lever is #### tough, but atleast you always know you will have 4wd when you need it.

Z71GUY Enthusiast

Z71GUY

Posted
Posted

I loved being able to just push a button to get mine into 4wd

Yeah, just wait until that POS push button quits working (And it will) and then see how much you like your 4wd setup.  I know that getting out in the cold to lock the hubs, and then having to yank on a lever is #### tough, but atleast you always know you will have 4wd when you need it.

Mine has been working fine for a few years and I know guys with older trucks, much older that still work fine.  I've seen the "manual" systems break too.  Its just like anything else, after time...it WILL break.

 

As for the question at hand... no, this does not mean they have a locking front diff.  This is the manual way of locking the front hubs..1 part of a 2 part system.  The second part is pulling the lever.  Your/Our 4wd system does this all with a push of a button.

MarkD Senior Enthusiast

MarkD

Posted
Posted

Locking the hubs engages the wheels to the front drive axle.  While unlocked, the wheels and the front drive axle can turn independently of each other.

 

"Pulling the lever" on the inside of the truck engages the front drive shaft to the transmission, therefore powering the front drive axles.

 

4wd engaged, hubs unlocked will provide power to the axles, but the wheels still spin free of the axles.

 

4wd dis-engaged, hubs locked will not provide engine power to the front axle, but the wheels will turn the front drive axle.  This will serve as a parasitic power loss.

Bob G. Enthusiast

Bob G.

Posted
Posted

I remember way back in the old days when I had a 78 Chevy (1984 - 1995), I would lock the hubs at the beginning of winter and just shift the transfer case as needed. That truck would get about 10mpg no matter what you were doing!!

 

Bob G.

varmint2506 Enthusiast

varmint2506

Posted
Posted
I remember way back in the old days when I had a 78 Chevy (1984 - 1995), I would lock the hubs at the beginning of winter and just shift the transfer case as needed. That truck would get about 10mpg no matter what you were doing!!

 

Bob G.

My first 4x4 was a GMC Jimmy. A full time 4x4, no lockout hubs. I didn't have the money to put a lockout hub kit in at the time. Boy now that I think about that, it would have paid for itself in no time with gas savings. It had a 400 sb and got 10mph on the highway.

Larry Enthusiast

Larry

Posted
Posted

I loved being able to just push a button to get mine into 4wd

Yeah, just wait until that POS push button quits working (And it will) and then see how much you like your 4wd setup.  I know that getting out in the cold to lock the hubs, and then having to yank on a lever is #### tough, but atleast you always know you will have 4wd when you need it.

I agree with Kansas Kid.  The electric shift transfercases are not very reliable.  

 

Push buttons are for girls!  :cheers:

varmint2506 Enthusiast

varmint2506

Posted
Posted

I agree with Kansas Kid.  The electric shift transfercases are not very reliable.  

 

Push buttons are for girls!  :cheers:

Even with a manual engage transfer case, you still have electronics involved with the front end. (post '87 models) You can make that manual if you want. They make a manual front engage kit for $100.00.

Larry Enthusiast

Larry

Posted
Posted

I agree with Kansas Kid.  The electric shift transfercases are not very reliable.  

 

Push buttons are for girls!  :cheers:

Even with a manual engage transfer case, you still have electronics involved with the front end. (post '87 models) You can make that manual if you want. They make a manual front engage kit for $100.00.

You’re preachin' at the choir on this one.  I worked in the Chev TAC in Detroit for a couple years in the drivetrain group before moving out to the field.  I am very familiar with the old front axle thermal disconnects and the later electronic axle disconnects.   Both of which are unreliable. Helped many of dealers fix these junks and have seen part turn data for the related part numbers from GMSPO.  Their making a killing on service parts for CADs, encoder motors and TCCM's even on top of warranty expenses.  You can see why the aftermarket has found a profit center with fixes for these replicated front axle CAD problems.  Now if only the aftermarket would come up with a manual shift dohicky to replace the encoder motors we'll be all set.

 

The manual locking hubs of the old days weren’t very convent for city slickers but were much more reliable than electronics.

Nobody wants a reliable 4x4 truck that they will actually take off road to the neverlands anymore…they all want a big gas guzzling all weather status symbol vehicles that they will trade off when the warranty expires anyway.  

 

Your right… the Posi-Loc cable front axle disconnects is the hot ticket.  Combine that with a manual transfercase and you’ll have a reliable 4x4.

BDBWTE Senior Enthusiast

BDBWTE

Posted
Posted
I agree with Kansas Kid.  The electric shift transfercases are not very reliable.  

 

Push buttons are for girls!  :cool:

Even with a manual engage transfer case, you still have electronics involved with the front end. (post '87 models) You can make that manual if you want. They make a manual front engage kit for $100.00.

You’re preachin' at the choir on this one.  I worked in the Chev TAC in Detroit for a couple years in the drivetrain group before moving out to the field.  I am very familiar with the old front axle thermal disconnects and the later electronic axle disconnects.   Both of which are unreliable. Helped many of dealers fix these junks and have seen part turn data for the related part numbers from GMSPO.  Their making a killing on service parts for CADs, encoder motors and TCCM's even on top of warranty expenses.  You can see why the aftermarket has found a profit center with fixes for these replicated front axle CAD problems.  Now if only the aftermarket would come up with a manual shift dohicky to replace the encoder motors we'll be all set.

 

The manual locking hubs of the old days weren’t very convent for city slickers but were much more reliable than electronics.

Nobody wants a reliable 4x4 truck that they will actually take off road to the neverlands anymore…they all want a big gas guzzling all weather status symbol vehicles that they will trade off when the warranty expires anyway.  

 

Your right… the Posi-Loc cable front axle disconnects is the hot ticket.  Combine that with a manual transfercase and you’ll have a reliable 4x4.

I would just like to say when I hear people like you speak your mind it makes me have hope for this world.

knuts Enthusiast

knuts

Posted
Posted

Just remember to lock them before you go too deep. Look at my website at the bottom under the 1990 blazer. Would you want to get out?!  At least the 1990 blazer had auto hubs and then the shifter inside to go to 4WD. I guess it was in between transitions of manual and automatic 4wd.

 

It took a while to engage sometimes also. :cool:

 

 

Also my old '74 blazer had the full time 4x4. I put the conversion kit in it and it gave it 2 low! Talk about sick torque, I think top speed was 8 mph and it sounded like a tank! Directions said whatever you do do NOT drive in 2 Lo. It was fun to stomp on it though, until I twisted the drive shaft apart in the middle. :crazy:

 

KK

HillHound Senior Enthusiast

HillHound

Posted
Posted

My F250 has ESOF and manual hubs.  The manual hubs are a backup feature in case the vacuum setup fails.  I've been driving pickups with electric TCs for years and I have yet to have one fail to engage despite all the talk of them being junk.  

 

I like the esof setup on the Superduty series better than any systems I've seen and if you want a dumb lever on the floor to make you feel like a man then you can keep it.  A manual-engaged TC with auto hubs can still fail so it's not as foolproof as some might think.  

 

Maybe we should all go to lawnmower type recoil pull-starters that come though the dash and do away with electronic ignition and starter motors.  That way when your truck's unreliable electric ignition fails you won't get stranded!  :cool:

Z71GUY Enthusiast

Z71GUY

Posted
Posted

I guess our trucks should have a manual crank instead of a starter and battery (we all know a battery does not last forever), this could strand us.  On the same note, we should go back to mechanical carbs instead of EFI systems.  Again, if the electronics fail, we could be stranded.  Basically, any truck made in the mid-late 80's and up are bad trucks because they use electronic controls that could fail and strand you.

 

The point I am trying to get across is that you cant fear technology.  If so, start buying up your older pickups and extra ones for parts.

varmint2506 Enthusiast

varmint2506

Posted
Posted
Your right… the Posi-Loc cable front axle disconnects is the hot ticket.  Combine that with a manual transfercase and you’ll have a reliable 4x4.

I switched my '89 over to that. I got tired of waiting for the POS thermal to engage.

 

I agree 100% on the reliability; unless you have an internal malfunction it's pretty much foolproof. :thumb:

 

:cool:

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