The Elephant in the Room

[cfg83]

Hiya Twerp -

Originally Posted by Twerp

Hello. A friend of mine told me about this site. I'm not sure if he's a member or not. He prolly will be as soon as he acquires a vehicle to ecomod. I've been checking it out for the past week and a few days ago I became a member. Currently I've got my V6 Tundra which I'm looking to moderately mod out. It's designed for fuel economy much like an elephant is designed for tight rope walking. If I can save up the money, I might try to get a cheap Geo Metro or something similar which I won't mind getting drastic with. The only other thing I have is a 94 Honda Magna, which I may end up trading for that Metro or something which would go a little better in the rain and the cold. For now though, I need help training my elephant on the balance beam.

Welcome to EM! I love that quote. I'm gonna use it the next chance I get. Your aero-brick avatar is spot-on too. I would read "Horton Hatches the Egg" for elephant balancing trickz :



CarloSW2

[Nerys]

Actually you can solve your 4wd problem easily and relatively affordably IF the option is available for your truck. When your NOT in 4wd the front shaft should not be turning but you are right the axles MIGHT be. Depends on your car CALL the dealer to find out.

If they DO look into after market HUBS for your car. You can get manually locking hubs or auto hubs (which your car SHOULD already have) to make sure the hubs unlock drive briskly in reverse for 30-50 feet. This should disengage the hubs and now your front wheels should spin freely WITHOUT spinning your axles of front drive shaft.

If yours do NOT have unlocking hubs you can look into after maker hubs.

[Twerp]

I sniffed around a Toyota Tundra forum and they were all talking about having to add either manual or automatic locking hubs because the stock hubs are permanently engaged. I'll do some research by jacking up the front end and spinning the wheels as soon as the weather gets a little better.

[Nerys]

If they spin try doing the reverse thing 40-50 feet stiff good acceleration (thats what my jeep needs sometimes to disengage the hubs)

IF that don;t work confirm with the dealer how there supposed to work and if always engaged look into new hubs. IIRC there not "that" expensive and should pay for themselves pretty quickly in both gas savings and driveline wear savings. Just make sure you "PUT" it in 4wd every now and then to lube up and grease all the 4wd components.

[Red]

Welcome to the site twerp, on the topic of hubs, a hub kit for you Tundra runs around $800-$1000 for parts alone, then depending you may or may not need new wheels if the hub doesn't fit through your center bore. Its driveway do able but I don't know how mechanically inclined you are. I know for TJs swapping the auto hubs for manual ones doesn't net that big of a gain. Something on the order of .5-1 mpg.

[Nerys]

WOW I do not remember them costing to much! I would definitely do the econ math before undertaking that project. I guess there a lot cheaper for older jeeps :-)

[Twerp]

I would have to see some estimates as to how many miles per gallon it would save me. Still, my gut tells me that I would not be able to justify the expense of a hub change. There's nothing in the owner's manual about reversing to disengage the hubs, so they are either permanently fixed or they just automatically disengage when 2wd is selected. I may still jack up the front end to figure that one out for curiosity's sake.

[Nerys]

Well there is one way to find out for sure. Depends on your car. Remove the hubs all together. Costs nothing and you can now test your MPG do some math and see if its worth it. Check ebay for cheaper even used unlocking hubs. $800 would make me seriously think twice. I would need it to be lower than $400 before I personally would consider it.

[Red]

Originally Posted by Twerp

I would have to see some estimates as to how many miles per gallon it would save me. Still, my gut tells me that I would not be able to justify the expense of a hub change. There's nothing in the owner's manual about reversing to disengage the hubs, so they are either permanently fixed or they just automatically disengage when 2wd is selected. I may still jack up the front end to figure that one out for curiosity's sake.

I know for the tacos the actual disconnect happens inside the t-case and not in the axle. Going to 2WD means that the gear set or the sprocket that drives the front shaft is just disengaged. The hubs remain locked no matter what. Older designs with actual manual hubs you could do the forwards backwards trick to get the hubs to disengage. The Waggy has a D44 up front so I think Ford stuff fits

Nerys, your XJ has the vacuum disco HP D30 right? You'd still be stuck using the Warn or Milemarker kit. On the Waggy you could just swap in manual hubs off another truck I think.

[Twerp]

Yeah, I'm pretty sure I'm going to abandon the disconnection of the front wheels at least for now. As soon as I can get a SG, I'll start looking into some aero mods first. I'm going to start with a Phil Knox style aero cap and then I might block off the front grill. From there, I might look into disconnecting hubs.