Help me understand front hubs, m'kay?
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Help me understand front hubs, m'kay?
I'm still new to all this, so bear with me. I believe I understand the logic behind wanting to have manual, rather than automatic/electronic hubs, especially when doing a suspension lift. My questions is, what do I have? I can engage four wheel from inside, but I wouldn't define whats happening/what I'm doing as automatic. I (and probaly a boat load of you) have a smaller lever to the right of my stick, which I presume is going to the transfer case. It certainly feels as though I am making a mechanical change, not initiating anything electronic (I've been in SUV's where you just hit a button on the dash), when I go into 4WD.
I'd love to get a clue.
I'd love to get a clue.
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Your question actually has nothing to do with hubs, automatic or manual. Toyotas since 1989 haven't had hubs at all, not manual and not automatic - the fronts axle(s) turn all the time, and instead use some form of front axle disconnect.
There are different systems, and someone with a Taco like yours can tell you for certain what happens when you pull that lever. (I quit bothering to keep up with the developments after about 1990, life's too shrt...) Here's one way it can work; Pull the lever and it physically puts the transfer case in 4wd Hi. There is a switch that tells a computer that you've engaged 4wd, and it then engages the front axle. Or another system might read the front driveshaft speed and wheel speed and when they match it engages the front axle.
Or, alternately, on systems like Ford with a simple switch on the dash for 4wd, when you turn the knob it first engages the front axle (again no hubs,) the front driveshaft starts spinning, when it matches the rear driveshaft speed the computer engages the transfer case.
There are different systems, and someone with a Taco like yours can tell you for certain what happens when you pull that lever. (I quit bothering to keep up with the developments after about 1990, life's too shrt...) Here's one way it can work; Pull the lever and it physically puts the transfer case in 4wd Hi. There is a switch that tells a computer that you've engaged 4wd, and it then engages the front axle. Or another system might read the front driveshaft speed and wheel speed and when they match it engages the front axle.
Or, alternately, on systems like Ford with a simple switch on the dash for 4wd, when you turn the knob it first engages the front axle (again no hubs,) the front driveshaft starts spinning, when it matches the rear driveshaft speed the computer engages the transfer case.
Last edited by Flamedx4; 08-01-2004 at 09:18 PM.
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Originally Posted by Flamedx4
Your question actually has nothing to do with hubs, automatic or manual. Toyotas since 1989 haven't had hubs at all, not manual and not automatic - the fronts axle(s) turn all the time, and instead use some form of front axle disconnect.
[/QUOTE]
Or, alternately, on systems like Ford with a simple switch on the dash for 4wd, when you turn the knob it first engages the front axle (again no hubs,) the front driveshaft starts spinning, when it matches the rear driveshaft speed the computer engages the transfer case.[/QUOTE]
So on (some) recent tacomas, the manual part I see is the axle connect/disconnect?
I guess I'll need an answer from somone with a newer taco....if I manage some nice juicy suspension lift in the future, is the method in which I engage my front axles something that will likely need to be changed?
Hell of paint job, BTW.
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Originally Posted by Flamedx4
Your question actually has nothing to do with hubs, automatic or manual. Toyotas since 1989 haven't had hubs at all, not manual and not automatic - the fronts axle(s) turn all the time, and instead use some form of front axle disconnect.
Not true. Some Toyotas still come with manual locking hubs. My brother's 96 Tacoma came stock with manual hubs. My 91 longbed came with manual hubs. The way you can tell that they came factory and weren't aftermarket is that the front axle has no sign of the ADD system. No vacuum lines, no actuator(the forks that engage the driver-side hub), no button inside. Some of us just got lucky with our Toy's.
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Originally Posted by OneTrickToy
Not true. Some Toyotas still come with manual locking hubs. My brother's 96 Tacoma came stock with manual hubs. My 91 longbed came with manual hubs. The way you can tell that they came factory and weren't aftermarket is that the front axle has no sign of the ADD system. No vacuum lines, no actuator(the forks that engage the driver-side hub), no button inside. Some of us just got lucky with our Toy's.
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Originally Posted by OneTrickToy
Not true. Some Toyotas still come with manual locking hubs. My brother's 96 Tacoma came stock with manual hubs. My 91 longbed came with manual hubs. The way you can tell that they came factory and weren't aftermarket is that the front axle has no sign of the ADD system. No vacuum lines, no actuator(the forks that engage the driver-side hub), no button inside. Some of us just got lucky with our Toy's.
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Originally Posted by roger
Yeah, my '98 has Aisin manual hubs. At least I can crow about having those since my truck didn't come with the e-locker.
#10
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all hiluxes were available with manual hubs from when they were first made until they stopped selling them in the US(think they're still an option in other countries)
tacos could be had with them until 2000 or so.
tacos could be had with them until 2000 or so.
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Originally Posted by kyle_22r
all hiluxes were available with manual hubs from when they were first made until they stopped selling them in the US(think they're still an option in other countries)
tacos could be had with them until 2000 or so.
tacos could be had with them until 2000 or so.
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For 2nd gen pickups (pre88) All models had Manual hubs and AUTO was optional
Hubs lock your wheels to your axleshaft.
Axle doesnt spin unless transfer case is in 4wd or your hubs are locked.
If in 4wd and hubs not locked, your axles will move but not your wheels.
I think this is right and its a great idea cause it causes the least amount of wear on your cv's and you can get a full time locker in front and not get wheel hop and stuff like that. Everything is on its own.
BUT, for 89 and up there is ADD, (automatic differental disconnect i thnk) and its way different. Above is basic and involved the least amount of technology
Hubs lock your wheels to your axleshaft.
Axle doesnt spin unless transfer case is in 4wd or your hubs are locked.
If in 4wd and hubs not locked, your axles will move but not your wheels.
I think this is right and its a great idea cause it causes the least amount of wear on your cv's and you can get a full time locker in front and not get wheel hop and stuff like that. Everything is on its own.
BUT, for 89 and up there is ADD, (automatic differental disconnect i thnk) and its way different. Above is basic and involved the least amount of technology
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I leased a '98 that had manual hubs. I should have bought it at the end of the lease but the way leases work forget it. It was a great truck. V6 5-speed 4x4 xtra cab.
#16
Originally Posted by ianshoots
I'm starting to think (based on past oberservation) that only single cabs, therefore only 4cylinder truck, came with the manual ....what? locking hub? locking axle? jeeze I need to start another thread to get the difference explained to me :pat:
All Pre 89's came with Manual hubs as standard equipment. An auto hub, which required you to back up after 4x4'ing to disengage the axle from the hub was optional. All pre 89 ifs diffs were interchangable (as long as gear ratios matched), as they didn't have the disconnecting diff at that time. In 89 they came up with ADD. The 89-95 ADD hubs could be made manual by taking off the locking plate and installing the Manual hubs. Easy swap. Same thing goes for this year, ADD meant no manual hubs, and vise versa. They also elminated and simplified the auto hub design, so rather than multiple moving parts in the hubs, it became just the locking plate which would lock the inner hub to the outer spindle.
In 95, they came up with a new hub design, which incorporated even less moving parts, and eliminated the locking plate. Now, it became necessary to swap the spindle assy, the axle, and add the locking hubs which of course is more expensive and labor intensive.
Hopefully that makes it a bit easier to understand. There was no code or procedure to follow as to which vehicle got ADD and which ones didn't. ALmost all SR5 4runners had ADD, and almost all Automatics had ADD. The 4Runners were becoming grocery getters heh. Thank god that Toyota makes all their parts interchangable. Simplicity rules in the game of offroad.
#17
Originally Posted by ianshoots
I'm starting to think (based on past oberservation) that only single cabs, therefore only 4cylinder truck, came with the manual ....what? locking hub? locking axle? jeeze I need to start another thread to get the difference explained to me :pat:
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My 1991 Extracab has manual hubs. Pain in the butt in bad weather to engage. I had a mechanic swear the design was the same as the old International military trucks. He was impressed.
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Originally Posted by colsoncj
this may be a little off subject, which if it is i'll start a new thread... but why are manual hubs better than auto hubs. specifically on my 87 4runner :-p
the day i bought my 4runner with autos i got stuck in a swampy cornfield with 2wd and couldnt move. Granted i shouldnt have been there stock as is only the rears were moving. Later that week I got manual hubs and had no problems with 4wd working after that.
PS - I will have some AISIN manual hubs off of an 87 for sale on ebay very soon.
#20
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i don't trust vacuum lines to do the work of good old manual linkage.
also, in '84 and '85 or so, TRUE auto hubs were an option, but they are garbage. ADD and auto hubs are different, add uses a drive flange and vacuum disconnect, while an auto hub just replaces a manual hub. to engage auto hubs, you have to back up. not the most robust system, but a lot of american companies used them until the mid 90s and nissan uses them on xterras and frontiers to this day
also, in '84 and '85 or so, TRUE auto hubs were an option, but they are garbage. ADD and auto hubs are different, add uses a drive flange and vacuum disconnect, while an auto hub just replaces a manual hub. to engage auto hubs, you have to back up. not the most robust system, but a lot of american companies used them until the mid 90s and nissan uses them on xterras and frontiers to this day