A4WD Grinding when turning issues

[wchain]

Hi guys,
I have a 99 Expeiditon A4WD that I borught into the dealer about 6 mos ago for a grinding noise and vibration in the wheel while turning. THey diagnosed a grocery list of things that needed to be changed, and wanted over 2500 dollars for the repair.

I took it to another place that replaced upper and lower control arms (with ball joints), sway bar end links, Front CV shafts, and performed an alignment.

The truck still does it, and it was worse in the rain, but it seems to do it all the time now. A 4WD shop diagnosed it as a shift motor and pulled the DTCs showing it was a shift motor, but declined to work on it.

Now, I ahve taken it to another ford Dealer in town who tells me "your CV Joints are Collapsed, and thats what's causing the grinding when turning. There is no grease whatsoever in the CV shafts themselves"


THe place that did the work in the first place is willign to replace the CV Shafts, since they are under warranty, but I just dont think thats whats causing the grinding.

Also, will someone explain how A4WD works? Is it full time or "on demand"?

Thanks
W

 

[rwinch]

Check out this post on A4WD, and the manual's explaination about it:

http://www.expeditionforum.com/forums/postings.php?s=&action=getip&postid=1814

 

[rwinch]

OK...that didn't work. I still need to figure out how to direct to another post!

Anyway, do a search on A4WD, you will find a bunch of stuff.

Here is what I was trying to show you:

I found the following excerpt from Autoworld.com.

"A4WD, in which Control Trac automatically selects between two-wheel drive and four-wheel drive as needed. The transfer case monitors drive-shaft speed and reports the onset of rear slippage. Should rear slippage occur, a computer-controlled electromagnetic clutch engages to add torque to the front wheel. If the rear wheels regain grip, the clutch automatically disengages. When slippery conditions persist at speeds below 35 mph, Control Trac keeps front drive engaged for five minutes or until vehicle speed exceeds 45 mph. This mode can be engaged at any time with the vehicle in motion."

 

[smo0othride]

here's the link

 

[exsport]

I am not sure about anybody elses specific problem with this issue, but i would like to offer a point of view (which is subject to change):
My initial impression of this "grinding" sensation is that it is completely normal in an all wheel drive vehicle. I have owned subaru's (2) and audi's (4) and the light grinding sensation when turning from a stop or at very low speeds when the vehicle is cold is something that seems to be common to all of them. My '04 Expedition does this just like all the others....with the exception that the condition is slightly more prominent when in 2HI than when in A4WD. None of my other AWD was able to shift to 2 wheel mode... but the condition was common to all of them... for that matter common to many a toyota and/or any other AWD vehicle...
In the case of my Expedition, the "condition" if it is that, is not very noticable and seems to have improved with age (only 14,000 miles, but definitely WAY LESS prominent than when the vehicle was brand new). Having said that, it has been the case with all of my AWD vehicles that the "condition" improves with age to a point where it either vanishes entirely or has become so faint that one would have to try hard to notice. It only happens on the first and sometimes the second 90 degree turn when the vehicle is cold. I think that generally it is best left alone!!!!
All of the guys on here that keep taking their BRAND NEW truck back to the dealer because of these little problems or because of some little jiggle or whine or any little ping or sound are INSANE!!!
I am sure that there are some out there with legitimate problems, but these things are machines... they make noise when they run... if you don't like the vibrations buy a Lincoln Navigator basically the same truck, but with lots more sound-proofing (and weight), or just fill the doors and all the other hollow spaces with styrofoam (literally), there are plenty of shops out there who specialize in that.... but don't let some numb-nut at the dealership open up your differentials and trannies and transfer cases!!! much less repeatedly!!!!don't let them keep taking your truck apart and putting it back together... I promise you that the end result of this type of paranoia will be that your truck will be messed up!!!! Think about it!!! Read these people's posts... the horror stories just keep getting worse.... the more times these guys take their trucks in for work, the more stuff goes wrong.... There is a reason for lifetime tranny fluids/ lifetime differential fluids (not sure if the Expy comes with these)/ lifetime radiator fluids/ synthetic oils/ extended service intervals.... Anyone see a pattern here? There have been multiple studies which show that the less times a vehicle is serviced (to a reasonable limit: oil does need to be changed, but not every 3,000 miles) the less problems there are. It is not because the shops are negligent, it is because if something is working it does not need to be fixed. Tearing it open and scratching your head just to put it back together and find nothing wrong leads to problems...
If you must try to fix this "condition" and insist that your truck must never shimmy, shake, whine, or grind in any way, then by all means do not let the dealer tell you that this problem is in the rear differential... it is not! the rear axle whine is a separate problem entirely!!! This condition of grinding while turning from a stop or at slow speeds and only when the vehicle is cold is a symptom of AWD and the front diff. The "spring" fix sounds like the best one for this symptom, maybe some friction modifier for the diff. fluid.
Maybe Ford needs a differential heater built it to the differentials to keep them warm so that the vehicles do not experience this...lol
Really guys, wait til your diff and half shafts seize and then get the damn thing fixed!!!!! In the meantime, if you think that this would actually happen on your vehicle, repeatedly call and write both your dealer and Ford regarding this issue to document it, many deealers will tell you it is not a problem ( and i beleive they are right) but if it does turn out to be a problem.... What do you have to be worried about??? Warranty? NO WAY... So many people are whining about this (and the brake dust) that we will all be able to clean up in a big class action lawsuit against Ford and our Dealerships for Negligence, wreckless endangerment, breach of contract, warranty of fitness for particular purpose, etc... They will quickly and quietly pay for all of our problems.
NO WORRIES MATES! AWD ROCKS!! WHO CARES IF IT EATS THE OCCASIONAL AXLE? THE REST OF THE TIME IT WILL BE KEEPING US ALL SAFE AND IN CONTROL OR ALLOWING US TO GO THROUGH WATER/MUD/RAIN/SNOW OR OFF-ROAD WITH EASE. NO BOUNDARIES!!

 

[bluebird1]

Hello all. I have a 2000 EB with all the problems known to happen, including the grinding while turning! I have read a lot of threads both here and on other forums and it is pretty clear that this noise is the result of the clutch packs in the rear differential. I know it feels like it is the front, but all other posts says it is the clutch packs and there is a TSB out for '03's. The advice I have read is to change out the rear lubricant, making certain to use the friction modifier from Ford. If this does not work, then apparently the only "cure" is to have the clutch packs replaced. I am going to tackle the lubricant change next week.