My new-to-me '95 will be plated this week, and it'll see 99% road duty. It's ADD-equipped, meaning the front end components all rotate continuously. Given the cost of gas, and the increased wear of ADD trucks, what's the concensus on installing manual hubs?

 

From what I've learned on YT manual hubs do little to none with mpg. I wouldn't spend that money. If it's a DD and bone stock I wouldn't worry about it. If there was extra strain on the hubs do it but here shouldn't be if it's stock.

 

The front differential always spins on one side, but its not connected to the front driveshaft until you go into 4wd. It does not affect gas mileage.

Unless there's a serious problem with your ADD to the point where it'll cost a ridiculous amount of money to fix, then I don't see the point in switching to manual hubs.

 

I agree. I switched to manual hubs last year and notice no difference in MPG. You will reduce wear and tear on your CV joints, but that's about it.

 

Well that sucks. I just got a set of manual hubs off of Craigslist, hoping to get a little better mileage. At least they were free, and it gives me another little project to do. I guess it's worth it from the wear-and-tear standpoint anyways.

Jason

 

If you have any lift on the front end that changes the angle of the CV's, ie. cranked torsion bars or BJ spacers, then go ahead and get the manual hubs. They will decrease the wear on the CV boots but if you plan to keep it stock then don't bother.

I'd bet that MPG increase with manual hubs is less than 5%, and that may even be a long shot.

 

I would. It gives you lots of options. You can run 2wd low range, saves your CV shafts because they will not spin when unlocked, if you break something in the front drive line you can limp home....IMHO

 

I noticed a slight increase in mpg when I switched; that combined with slight increases all across the board from other "that won't help" improvements has gained me a couple mpg in the long run. I think a new O2 sensor might even give me another .5 mpg & bump me up near 17 mpg.

I feel even though the increase was just in the .25 mpg range it was worth it in the long run since manual hubs can be had for in the neighborhood of $50 used & installing them is easy & only takes a few minutes.


Edit: if you want to call BS on the $50 price tag; talk to dirtoyboy; a member on here. He can get you the hubs + a rebuild kit (new gaskets & cap bolts) for around $60 INCLUDING shipping - give or take a few $$$ I'm sure depending on where you live.

 

Went over the schematics of the ADD again last night & see how it'll only spin the spider gears. Turns out my VSV that controlled the pull-off of the ADD was stuck, thus I was always engaged in the front, and the shaft would turn. Replacing that VSV (passenger side fender) feels like it free'd up a few ponies. This was all on my '91, although the original application was for my '95.

For the possible failure point of the hub, I don't think the ½ mpg is worth it at this time. 2WD low can be achieved by putting an interupter switch controlling the ADD 'engage' VSV. Power would transfer up, but the sleeve would not make the connection. Hmmm.... do I smell a cheap mod contribution???

 

You can put them on, if you want, then run a vacuum line to the actuator and be done with all the VSV BS.

By the way, anyone need a set of used VSVs?

 

I like the manual hubs for the boot wear but also you can disconect the tire from the cv in a case of cv failure. This make limping home a lot easier.

 

if your looking for fuel savings look at headers and exhaust mods and air induction mods. if you do a lot of highway driving look at slightly larger tire and lighter wheels. with all these mods i get about 18-19 mpg without changing driving habbits. i drive 60 miles a day at 70-80 mph. if i keep my foot out of it i could probably get 20mpg.

 

I just prefer manuel hubs cause i had the factory auto lock on me when the front end wasn't locked.

 

Just keep an ADD plate & you don't have to worry about a "possible failure point at the hub".....Aisins aren't known for weakness anyway but having the ADD plate negates any worries one might dream up.

 

If the truck is 99% on road, like you mentioned, I wouldnt bother.......