How to properly use 4WD

[Idealconcepts]

Ok, I have 1989 4WD V6 Manual Toyota Truck with approximately 181, 3XX miles, bought it about a month and a half ago when it had about 179,7XX miles and everything seems to be working great on it. When I purchased the truck from the original owner he stated he used the 4WD occasionally each year, they would take it up to their cabin and need 4WD to get through the snow. I did a search on this topic and was not able to find all answers to my questions and wanted to see if you guys/girls can answer them or post a link to a thread that has the answers. I understand some info will be in the owner’s manual but would like to also get first hand knowledge from people as manual’s sometimes aren’t very descriptive. My questions:

1. The owner had his front hubs in the locked position and I have left them there ever since. Will I be causing problems to my truck if I drive in normal 2WD (2H) mode with the front hubs locked all the time? What problems would I be causing?
2. I want to test out the 4WD (which I should have done with the owner but forgot) to make sure it works but very nervous I might do something wrong or advance an already existing problem. What I understand is not to use 4H or 4L in dry pavement/cement/asphalt. Please correct the following if I mis-understood: 4H is for driving on wet, icy, or snow covered pavement/cement/asphalt and 4L is used for climbing/descending steep hills, off road driving and hard pulling in mud, sand, deep snow. My question is when I shift from 2H to 4H, I need to first lock my hubs (which they already are, but will unlock them if this is bad to drive with locked hubs all the time), when I shift it into 4H do I need to make sure the truck is not moving and the wheels are not spinning? Does this apply (stopping the forward motion of the truck before shifting) any time I shift between 2H, 4H, 4L gears? Also the clutch is not involved with any of this correct?
3. Is there a recommended speed that I stay under when I am in 4H or 4L?
4. Anything else I need to be aware of or cautious of when I first try 4WD?
5. I more than likely will not use 4WD very often, but how often each year should I engage 4WD to make sure it continues to work properly and for how long (miles/mins)? (i.e. once a month, once every 3 or 4 months, once every 6 months, once a year)

Thanks in advance for you help.

[2tacomas]

1. First thing you need to do is unlock your front hubs- always keep them unlocked when you are not using 4wd.
2. 4 High vs. 4 Low: use high for driving in snowy conditions or when you are going down somewhat rough offroad trails in which you can go somewhat fast (20mph or faster). Think of 4 low as 1st gear on a manual transmittion, use that when you need extra power but will not be going fast (i.e. trying to get yourself out of a nasty mud hole or very loose sand...basically situations where you are not going to be driving at a high rate of speed (anything under 15mph)
When shifting from 2h to 4h, stop your truck..lock the hubs...put your truck into neutral and then into gear- you may need to put it into reverse if the 4wd does not kick in, let your truck roll back about 1 revolution of the tires and it should go into 4wd.
3. I would not recommend going faster than 65mph in 4h (that is really flying in 4wd anyway) and as for 4L- keep it under 20mph (15mph and under is even better)
4. Make sure you are not on a hard surface- go into a field somewhere and try it out. Like I said earlier, if your truck does not go into 4wd after you have locked the hubs and taken it out of neutral, put it in reverse (or if you are at a step angle just roll backwards) and back-up about 1 tire revolution and it should go into 4wd.
5. Ideally, you should try to use the 4wd on your vehicle for atleast 6-12 miles every oil change (6-12 miles for every 3,000 or so miles) most people do not do this, but as long as you engage the 4wd at least once every few months and use it for a few miles, it should be enough to keep all of those parts lubed and in working contition.

Good luck and let me know if you have any more questions.

[Idealconcepts]

Thanks 2tacomas, I really appreciate the detailed explanation on how to do this use 4WD correctly. I have two additional questions though.

1. What am I doing to the truck driving with the hubs locked but not driving in 4WD? I will go unlock now, but just want to know what it does to the truck when it is locked and 4WD is not being used.
2. When I shift from 2H to 4H or 4L, I put the normal 5spd in neutral, then shift the 2H/4H/4L gears into 4H or 4L, then drive it normally? Is this correct?

Thanks again.

[reb]

I agree with most of what 2tacomas said. However, you are not harming the truck by leaving the hubs locked. Hubs were virtually unheard when 4WD first became popular, back in the '50s. Unlocking them will reduce wear in the front end and probably help your gas mileage. Also, if your tire pressures are about the same (the tires must all be the same size) you can go from 2WD high to 4WD high and back on the move (with the hubs locked); just let up on the gas when you do it. Shifting to or from low range requires you to stop and put in the clutch first.

Another thought: Driving on slick roads can be squirrely with 4WD engaged. If you approach a curve and back off the throttle as you would with a 2WD, the front end can lose traction and cause you to spin out, as I found out on a snow-packed Colorado mountain road a few years ago.

[2tacomas]

1. I do not think that it physically damages the hubs to have them locked in while you are driving, but your truck will burn more gas with the hubs locked in.

2. After you have locked the hubs in: put your truck into neutral (with the 5 speed column), then (with the 2H-4H-4L shifter) shift the 2H shifter into 4H. When shifting into 4L you have to put the 2H-4H-4L shifter into neutral, and then you push it forward to the 4L setting (the way the shifter is set up you have to go through Neutral on it before you get to 4L anyway) and then put the truck into gear (with the 5 speed shifter). Just remember, if it doesn't go into 4wd, let the truck roll backwards about one revolution of the tires (while the 5 speed shifter is in neutral and the 4wd shifter is in the gear you want it to be in) and that should do the trick.

[Idealconcepts]

Thank you both reb and 2tacomas for the information, I really appreciate it. I think I will keep my hubs unlocked and hopefully I can get better gas mileage. The previous owner put 31's so from what I understand larger tires will reduce gas mileage slightly. I going to test out the 4WD this weekend on some dirt or muddy areas. Thanks again.