Are manual hubs really worth it?

[Pskhaat]

I came into some aisin hubs during a recent used parts visit for some other stuff for my 40. For those that have done this manual hub mod, is it really worth the effort? Has either your fuel mileage improved significantly or have you been able to limp away from breakage any better due to the manual hubs?

Thanks,

 

[CruisinGA]

You will see a gas mileage increase only if you remove the front driveshaft as well, or install a part time conversion that allows you to disconnect it.

With just hubs unlocked, the transfer case is still spinning all that mass in the front axle.

Also- if you want to sell the hubs, I will buy them.

 

[clownmidget]

if you read through the threads on them then you can tell that there is no real increase in fuel mileage with them. all that mass is still all that mass. I ran them on my 97 with the front driveshaft removed and the CDL engaged and noticed no difference in fuel mileage but as Robbie and others from way back wrote, the front end felt "lighter". Doing it does save wear and tear on the front axle bits spinning all the time but defeats the full-time 4WD benefits and ABS. My reason was to hopefully allow me to limp home if I blew up a birfield. Unfortunately the classic birfield failure (cage exploding) allows the outer shaft stub to move out (sometimes forcefully) and chewing up the inside of your hub dial. So you now have a ruined hub and a blown birfield. for now I'm back to using drive plates...

 

[Tapage]

If you go with hubs front .. I thought maybe it affect the center diff operation .. the Visco C thought the front tires are spinning . ?

 

[LandCruiserPhil]

Aisin do not provide proper clearance later 80's long outer shafts you run the risk of chewing up the dials face even without a birf failure. If you are set on running hubs on a late model 80, Warn hubs will provide the clearance you need.

In addition to Clowns post if you blow a birf the dial does not help much. You should remove the broken birf to keep your steering from binding.

 

[aim]

On my '92, unocked hubs also resulted in some vibration. Locking the hubs (all else being the same) made the vibration go away. As did rebalancing the tires...

 

[kenton]

On my '97, manual hubs and no front driveshaft gave me 10% better gas mileage (so the hubs became free after about one summer of driving), and give me peace of mind that I am getting around a flawed Toyota axle seal design by not spinning my front axleshafts.
However, also be aware that some people have suggested that the added lateral birf-spindle slop (something like 0.27") caused by manual hub differences from plates leads to premature wear, of the axle seal IIRC.
Kenton