4 WHEEL DRIVE NOVICE

The manual (P 374) for the Tundra (2022) recommends the truck be driven at least 10 miles per/month in 4H- changing the transfer at speeds not exceeding 62 mph.

I began my 10 miles for the month this morning and noticed when maneuvering into a parking space the truck made odd noises.

I found out from my mechanic and for those who may not know- the front axles don't turn easily at 90 deg in 4 H- is this the case?

This would have been good info for a 4W drive novice such as myself to know. Unless I missed it from the manual.

 

You want to keep the 4wd in straight line only on non-slippery surfaces. Gears tend to bind when turning on pavement. In snow or on dirt roads it is a different story since it allows the tires to effective slip when turning.

Even on dirt and snow you still want to be careful turning

 

You missed it in the manual. First line, “when driving on normal hard dry surfaces, use 2wd”

 

Dont drive in any 4wd mode on dry/hard surfaces....do it on a dirt road.

 

Can dirt not be hard and dry?

We can't all be offroad kings like you.

 

Fair enough... thank you for all the feed back!

 

It's perfectly fine on dry hard pavement in a straight line. I do it on a straight stretch of highway every now and then.

 

I have honestly only remembered to do this a handful of times in 20 years driving 4wd trucks and never had a problem with a 4wd system. Including my 09 Crewmax purchased new and trade at 113k and 13 years. For the most part my trucks have stayed in 2wd between late February and November.

I also do transfer case and diff fluid changes by 60k at the latest as a habit though. Usually more like 40-50 for first one.

 

I start doing this every week or so, for about 2 mile drive in a straight line.. Speed under 40 mph.

I then start getting whining noise when driving above 76mph on highway... In 2wd of course.

Coincidence or something didn't like me driving in straight line in 4wd on asphalt?

 

It is in the book, but you're probably didn't hurt anything from only doing it once. Just pop it into 4WD on a straight road for a mile or two every so often and you'll be good. It doesn't have to be 10 miles all at once. When in 4WD you don't want to turn much, especially sharp turns, unless you are on a surface that will allow the wheels/tires to slip a bit to prevent the binding that you experienced on the dry pavement.

I have about a mile of straight 55 MPH highway and another mile of straight 35 MPH dirt/gravel road in my commute. If you've got a mile or two of straight roads on your drives you can do the same thing I do. I'll pop it into 4WD once I'm turned onto the dirt road from my driveway, cruise the mile to the intersection with the highway and disengage 4WD as I am coming to a stop. Turn out onto the highway, and pop it back into 4WD once I'm traveling straight again. Then I just pop it out of 4WD before I turn off the highway to prevent any binding. The 4x4 system gets it's work out, and I don't have to worry about hurting anything so long as I am cognizant of the engaging and disengaging before making any major turns. A gradual turn in a road isn't going to hurt anything, but making a 90° turn off the street or into a parking spot is a no no.

 

Dirt roads, in general and no matter how hard, have a loose top layer allowing tires to slip. This is very important for four-wheel drive systems that lock the driveshafts, like Tundras/Tacomas and the like. Not an issue for AWD systems. BTW, it is ok on paved road if it is icey/snowy. Somewhat ok on wet roads in an emergency.

 

100% bullshit. I live on one, and after they douse it with mag water it hardens up and is not soft enough to allow slipping wheels. The only time it is soft enough is shortly after a repair run when they leave the layer of gravel on top, but that only lasts a few days before it's down to the hard packed dirt that is not soft.

All the dirt roads in your area or your experience may have a soft upper layer, but that is not the case everywhere.

 

@GODZILLA Ouch, 100%, really?! I did say, “in general”.

 

You said "in general" and immediately followed it with "no matter how hard" so that's not being clear enough for someone who is admitting to being a novice. It gives the impression that all dirt roads are going to be fine for 4WD turning, and this just simply is not the case. I could have said it in a more PC way of "that's not true" or "that's not always the case", but being PC in everything muddies the waters. As my grandfather used to say, "don't drag your feelings out behind you and they won't get stepped on."

I'm just trying to make sure the OP has all the correct info, because he openly states he doesn't know what is and is not ok for his 4x4 system.

 

So this occurs only after having driven it in 4wd first?

 

This whining noise happens now all the time above 76mph. Or if I Rev engine at neutral above 2k rpm. I don't use 4wd anymore at all.

This may or may not be related to me trying the 4wd on the road in a straight line, but I don't think this whine happened before I start doing this preventative maintenance once in a while

 

If it's making it in neutral that would seem to rule out the transmission.
You think it would be the turbos kicking in?

 

It doesn't sound like turbos, turbos are whoosh sound, very distinct and I like it.
This sound is just whining sound and only happens when I press gas pedal, when rpms above 2k or when pressing gas pedal above 76mph.

 

Something to do with the devil's lettuce, I'll wager.

 

Turbos don't whoosh. Wastegates do. Turbos 100% whine.

This has nothing to do with you using 4WD.

 

4x4 HI on these Tundras can be super annoying to get in and out of. Toyota must have a very conservative engagement/disengagement sequence. It can result in binding around corners like OP when you’ve selected back to 2wd a minute ago. (Or like on TFLtruck has demonstrated, you can be stuck in 2wd then flip on 4HI and watch it blink and never engage haha).

 

I accidentally drove my Tundra in 4H on pavement to the post office thinking I was getting my "10 miles for the month in"- before I read this tread. My speed reached up to 40 mph with slow acceleration more like 37, I drove total about 2.5 miles, I made wide turns and didn't hear anything. I did park however, but it was a wide maneuver. I drove back to the office and before I parked- I had a feeling that I should put it back in 2H... and I did. I did hear a little noise from the front end while parking. I read the thread shortly after.

After reading the thread of "do"s and don'ts" - I took it for a test drive and it performed great... no noises... strong acceleration... the transmission's smooth...parks well... the front-end handles great! I've only driven this truck 6 days and my previous truck was a 2007 SR5 V6 272K miles. As no surprise, I'm really enjoying the overall performance of this truck. This truck was a personal gift to myself.

How concerned should I be that I broke something?

 

Unlikely that you broke anything. Take the truck to a dirt lot, with loose dirt, and put it into 4WD and see if you get any binding, grinding, or popping. If it drives in 4WD fine, then you should be fine. Still, don't do tight turns in 4WD if it's avoidable.

If you want the whys, try this video.

https://youtu.be/4-Wy5ENm_lM

 

Thank you for the advice. I have watched countless videos since the 3rd Gen came out demonstrating these trucks in 4WD drive on obstacle courses going over rock and holes and not once did I hear a warning about "you don't turn the front wheels at hard turning angles." I'm watching the wrong videos.

 

We all learn somewhere. That guy's yootoob channel is a fairly good resource if you want to get into the engineering and reasons why for lots of mechanical stuff. Understanding what the 4WD system is doing will help you know what is and isn't ok for it, but Tacoma's aren't made out of fine china. I'm pretty sure you didn't hurt anything with your learning.

 

Thank you for the video.

 

So you think that it's turbos that do the whining sound when I accelerate slowly above 76mph or Rev engine in neutral above 2k?
Doesn't sound normal

 

I have no idea what is whining in your particular truck. I'm just saying that turbos do whine. Also, if you are in neutral and can replicate it then I can't see any possible way it is related to your 4wd system.

 

Now, I can't speak for these trucks, but I did find these when searching for turbo whine. I drove diesels/semis for several years, and different engines had different amounts of turbo whine, and my WRX had a much quieter whine, so I don't know that I'd think it's a failing turbo if it's always been there. With yours just starting up, you may want to get the turbos checked while you are still under warranty.



Turbos do spool up with a whistle/whine though.