A few weeks ago I was playing in my truck had had problems in 4wd. The dealer said there were no trouble codes. So, I decided to take it beach to out yesterday and test and dod some troubleshooting myself. I went to the beach and put it in 4hi and walked around and no problems, tried it in 4lo and no problems again so I figured it was a freak accident. I was on my home and a couple of buddies spotted me driving down the road. They gave me a call because on of them want to play in the mud but he has a stock Tacoma 4x4 and just wanted some to be out there in case he got stuck, so like a good guy I turned around. I convinced him to play in the sand first. since my truck was working fine (I thought) I started to show off playing in 2wd and ended up digging my rear wheels down. I shift in to 4lo by the books and heard everything lock up. I gave it some gas and started to come out of the holes and BAM the front hubs come unlocked then I hear a little bit of noise from them as I let off the gas and then BAM they relock. This continues to until alltires are free wheeling and my side steps are on the ground along with wy rear axle and lower control arms. I was with only a tacoma with me. So we got a old Bronco with 36's to pull me out, but he couldn't. But he did call call his dad that came out with a 77' Ford with 3/4 ton axles with5.16 gears aqnd locks front and rear wearing 44" ground hawgs powered by a 460. He had to pull on me a couple of different times. But back to the problems I am having, I read something about a vacuum valve fai;ing or something like that on early models. (My build date 02/04) And can anyone give me a descripition on how our front hubs work. Any help is appreciated.

 

Here is the hubs that are on the truck. You might try nosing around the Warn web site for more info.

https://www.f150online.com/forums/li...heel.End.shtml

Also the default position (no vacuum) is locked. It may be that the solenoid is sending vacuum when it shouldn't.

 

Thanks KingFish

 

Anymore Help

 

If you're driving down the road in 2wd and the vacuum fails, would the 4HI light come on without the switch being rotated there? I'd hate to be driving around on pavement with 4wd engaged and not knowing it (though I'd imagine you'd eventually feel it).

 

I am pretty sure you would feel it, especially in a turn. It may even give you some noise, due to the fact that the wheel is turning the axle/driveshaft, not the other way around. Also, if you have no vacuum, probably 10 other things aren't going to work right either. I don't believe the 4hi light would come on. Someone else may be able to verify.

 

Mine has done the same thing several times, luckily I was with others when it happened or I would have stuck in mud in the middle of nowhere. Dealer has not been able to duplicate the problem and has told me everything is normal. It's embarrassing and frustrating to have a 4WD that doesn't work, a friend of mine with an 05 SuperCrew has had the same problem once and was told the same thing by the dealer. His father in law is a mechanic and is going to look into the problem on his F150 next weekend.

 

Hey Turilla,
Let me know what is found out.

 

Will keep you posted. As of today, my buddy has his F150 back from the dealer with everything supposedly working. They told him point blank that if the 4WD works in the shop and there are no codes stored there is nothing they can do. The problem is that ours have never generated problem codes, he tried going to 4WD tonight and it failed twice out of 4 attempts, it is going right over to the shop in the morning so as soon as I hear anything I will let you know.

 

To clear up things, I just took vacuum readings at the hubs and it is 20 in. and 0 engaged. I shifted in and out of 4wd multiple time 4hi and 4lo. everything on the vacuum sides appears to be sound.

 

what ever happened i think i may have the same problem, i get a high whine like metal on metal almost like the hubs are trying to lock, if its not that it may be my bearings, but i think it is the 4wd b/c it only does it every other time i am in the truck

 

Exact problem here. It might be internal tcase damage (chain slippage, fork not engaging completely, broken gear teeth, etc). To help the guys who gave you advice with their problem, see last paragraph (I started typing before reading your problem...just their responses).

I still have found no direct solution to the problem, I'm near certain the tcase has internal damage...and not just the shift motor. Does your Tcase disengage when under load (e.g. after any load is put on the drivetrain, uphill or in sand, etc). I am going to tear down my tcase and find out. To test this, have someone get under your truck and have you go up a hill...have them focus on the front driveshaft. As soon as it disengages 4wd your front driveshaft should stop. That means it's from the tcase back, if not it's possibly the hubs, etc. That's cheaper but not likely. Give us a report back.

A way to tell if it's the shift motor, take the shift motor attached to the tcase off, and manually engage that rod...it will be evident which is 4lo, 4hi, etc. This will tell you if it's internal or just the shift motor (about $100). You can get a tcase for around $400 @ car-parts.com, maybe cheaper maybe more.

I believe these BorgWarners are pretty weak when placed under load. A lot of heat buildup in gear reduction while engaged in 4lo. There is not enough gear reduction for our tires at the axles...if this is the case then regearing is the solution so the axles are the bottleneck. I have posted this on answers.com, everywhere. I've searched manuals for all types of borgwarner tcases and the symptoms are there, but every solution was to tear down. First things first ayresun, remove that shift motor and manually engage the tcase and see if the symptoms persist...this is easy and cost effective.



You will not feel anything out of the ordinary when your hubs are engaged, it's different than being locked into 4wd. If you have no vacuum there are many ways to tell. Put your truck in 2wd and get under your truck, if while driving your front driveshaft spins then you have a problem. Check your fuse (I believe #11). Let me know what happens.

 

Might be the 4x4 solonoid. Mine would try to engage every so often while drinving making a horriable metal sound. Got this replaced and never happened again. think there is a TSB on this prob.

 

thanks i went to ford today and picked up the part, i changed in the parking lot since they wanted to charge me $60 to put it in (took me short of 1.5 minutes to do it!) no more sounds!! i have been living with this for a month now thinking it was my brake pads! glad it's fixed

 

you went within five minutes of him saying this? Quick response lol. Unless your hubs are damaged you shouldnt' be getting clanking from the front end when there is no vacuum pressure (engaged). To test the solenoid there are 2 lines, disconnect them and feel for pressure on the tips of the rubber hose, with the key in the on position. Also listen for the solenoid to engage (pretty loud) when you turn the key on, have someone do this in the truck and go under your hood while he turns the key to on then off. There should be a very clear clicking when the solenoid engages...the solenoid is on the pass side firewall.