Keep hubs locked all the time....

I have kept the hubs locked on my 1999 Tacoma 4x4 for about 6 months
now. The only problem I see is a little less gas mileage. Is there a
reason not to do this?

 

It keeps the axles, diff, driveshaft, and part of the T-case spinning which just means they will wear faster. How often to you use 4wd?

 

Not supposed to go over 40 or 50 mph with them locked. Also things wear out quicker. Lock them just when you need 4wd

 

On the other hand, the front driveshaft U-joints are well lubricated.

 

I trashed the t-case in my '95 doing this. Like an idiot, I would lock them in November and leave them that way until spring, at all speeds. It tossed all the gear oil out the top of the t-case and destroyed it over time. I had to replace it once I lost 4WD. It wasn't even worth trying to diagnose or repair.

It's hard to understand why folks do this (and I did, so I point the finger right back at myself.) Those of us with ADD want to do manual hub conversions so we can let the front wheels roll free, and manual hub owners often want to leave them locked.

It's unnecessary wear and tear on the entire front drivetrain. It's worth the effort to lock and unlock them only when needed. There's no sense in wearing out those moving parts out of laziness (which is why I left mine locked. Like an idiot.)

Go out in your driveway right now and unlock them. I'm not just running my mouth. I've been there and paid the price.

 

If its drives fine, it's fine. On second gens, they are permanently locked. All that stuff is spinning all the time. It's not a big deal.

 

No, no, no! It's not fine!

There's a reason Toyota told us not to do it, and put a speed limit of 50 on it. Wear and tear, man. There's absolutely no need to wear sh*t out when it's not needed. I'm telling anyone looking at this thread - I've trashed a t-case by doing this. I know what I'm talking about based on my first hand experience with my 95.5. I'll never forget that cold day laying in a friend's driveway wrestling that grease-slimed t-case out from under the truck, all due to driving with locked hubs unnecessarily.

It is not fine. It is a big deal. It will break sh*t over time.

 

The front driveshaft doesn't spin in 2H on 2nd gens. From GLD01's post, it seems a spinning front driveshaft while disconnected inside the transfer case causes lubrication issues for the transfer case.

 

Yes sir, it does. I promise you. I wish I'd taken pictures of it. The entire t-case was covered in oil/grease slime. It wasn't a leak. The only way that happened was by churning it out the top.

I've tried to tell people this on here before, but folks who have never made this mistake have no idea what they're talking about and try to ignore what I have to say.

Don't make my mistake. Get your ass out of the truck and lock 'em only when needed, and then get your ass back out and unlock 'em when you're done. I kicked myself for a long time for being lazy and tearing my truck up in the process.

 

Is the transfer case open at the top in 1st gens? Where was the oil coming out from?

BTW, where does the owner's manual state a 40 mph or 50 mph limit for running with the hubs engaged in 2H? Section 1-6 of the manual says you shift from 2H to 4H at up to 25 mph after the hubs are engaged. The limit for shifting from 2H to 4H for models with ADD is 50 mph. http://www.toyota.com/t3Portal/document/om/OM35751U/xhtml/OM35751U_OM0006.html?locale=en

 

No, it's not completely open, but it's not gasket sealed, either. The sludge that covered the entire thing was worst at the top near the opening for the levers, and coated almost the entire t-case. It was nasty. I have always very, very highly suspected that the many winters I locked those hubs for months at a time, at all speeds, churned the gear oil enough that it found its way out the top and coated the t-case, and led to some kind of internal failure.

This was my experience. And the bottom line is that everything from Toyota suggests judicious use of 4WD only when necessary, and specifies a speed limit of 50 mph when doing so. Those guidelines aren't arbitrary. And even outside of those guidelines, if you care at all about your vehicle, there's no justification for unnecessary wear and tear in daily driving.

 

Gear oil would come from the shifter seat or breather if hes missing a oil slinger. If your running long distances at hwy speed it might cause some ware over a long time. The gear oil will be circulating more as the front shaft/chain is spinning locked, it wont in 2wd/unlocked. Old tcase fluid and a bad shifter seat/slinger would def cause the leak tho, then your oil is moving more when locked, leave you with less fluid and fry ur case eventually.

 

Not too often, but I like to have it ready all the time. Like when I'm on a wed road and need to pull out into traffic. The wheel spin is terrible and I can't speed up to the flow of traffic.

 

Thanks, I just did it. Seems like they would warn you about that in the owner's manual. Thanks for the tip!

 

That's what I was thinking, but some don't agree!

 

Any time.

I wouldn't feel or talk so strongly about this one if I hadn't had the experience I did by doing this. It was the kind of thing where a little bit of hindsight left me kicking myself really hard for not putting in a little effort to take care of that truck a little better. I know it may seem less than ideal to some to have to lock and unlock the hubs when they are and aren't needed, but in the long run it's worth it. I promise.

And that's what I did. I'll admit - Maybe it's OK to leave them locked for a truck that never sees highway speeds or long distances (I personally wouldn't do it.) But what I did was abusive. Months at a time, at all speeds and long distances. I think that's where the damage was done.

 

Is there a way you can crop that photo differently so we can see a little lower on the swim suit?

 

Yes driving with your hubs locked is fine. I really don't see the point to it unless your an Off-road trainer but it's not going to hurt anything. If you have ever been in a Toyota transfer case you would know that it is ludicrous that driving with the hubs locked would cause a failure. My guess to whoever broke there tcase was due to improper lubrication or other issues. Also Toyota cases are pretty sealed up only possible places for a leak is the vent or the shifter.

 

Also if you want the add stuff I'd be will to trade, I prefer manual hubs over add/cad

 

There seems to be a lot of mis-information in this thread.

This is not correct. Simply engaging the front manual hub causes the axles to turn inside the diff. The only way the front driveshaft would also turn is if the front diff has a locker engaged. Stock, open diff setups will not turn the front driveshaft.

I call bs on this being the cause of your trouble. Do you have and ARB selectable locker or an auto-locker in your front diff? That is the only way the front driveshaft would turn when your hubs are locked.

The t-cases in the 1st gens do seep fluid out of the top gasket. Tho, I've never found it to be enough to cause a problem if you change fluids on the recommended 30K interval. Failure to monitor fluid levels might lead to consequences like you have described.

This is the same for 1st gens with ADD. As I've said ^^^, only a locked locker changes this. The diff is open otherwise.

So at that point you engage your t-case by moving the lever (or button) to the 4hi position, right?

Personally, I would take the time to engage only when I need to but, IMO, you can leave your manual hubs engaged all the time if you choose to without having to worry about causing unnecessary wear and tear on wheel bearings or diff bearings.