Jpielert97

Hey all, I am having a problem with the front right CV axle on my truck. It is a 1997 with the 4.6. A few months ago I replaced the front right CV shaft because a boot had been torn for a while. When I installed the new one I noticed that the wheel would not spin freely while on the lift, like the cv joint was locking up. I returned that shaft and got another one, same thing. This time I rolled with it, the wheel spins free when the weight is on the suspension. Recently the front axle tube that goes from the front diff to the CV shaft cracked in half. I replaced it and noticed while the truck was on the jack stands that the wheel is still locked when the suspension is extended. If im going 40mph or above and turn sharp to the right the whole truck shakes like im hitting pot holes. I believe this to be the cv joint locking up. I know this is what caused the axle tube to break, I can see the whole tube flex while on the jack stands.

I have the torsion bars cranked so I assume it creates too much angle for the cv shaft, but I had no issues with the original shaft.

Is there a better axle brand or a different axle? I think i read once before expedition shafts had more movement or something, I dont want the front axle tube to keep breaking.

Any help would be appreciated, Thanks!

fordguy2100

Are you sure your 4x4 isn't engaged?
With your torsion bar crank your measurement from center of hub to bottom of fender should be equal to or less than 24.25". If you're there or less your angles are fine and there's nothing to worry about.

Sure sounds like you're locked in 4wd...
Have you noticed a drop in fuel mileage?

white89gt

If you have the factory CV still, have it rebuilt be a local shop. Aftermarket CV's are junk - even the "new" axles. (Unless you get a Motorcraft New shaft)

I agree with 2100's assessment that your axle seems to be staying engaged.

DarrinT04

that does sound like the 4wd is engaged. it is hard to turn sharp when in 4wd because the cv's are trying to turn the wheels and a sharp turn puts strain on the cv's. it is called binding. because you are going so fast in 4wd you will feel vibration coming from the cv axle. going slow off road you won't notice it as much but turning at 40 mph on asphalt in 4wd, you will feel and hear the effects

Jpielert97

Ok, I went out and measured, exactly 24.5 inches from fender to center of hub. I tested the 4wd by turning all the way in my driveway and it went no problem, engaged 4wd and it wont move all the way turned. Pretty certain 4wd is disengaged when the problem occurs. I wish I had the old cv still, sent it to scrap. Im thinking about getting a junkyard shaft and seeing what that does. Fuel mileage has stayed the same.

fordguy2100

Wonder if the sensor for the auto locking hubs has a short or is going bad cause it to engage?

I know it's not the problem you posted for but it seems like your symptoms are what happens when 4x4 is engaged...
https://www.f150online.com/forums/tr...es-itself.html

Only other thing I can think of is the cv axle is really that crappy that you're having all these issues. You can try the sensor, it's $25... don't know what a junkyard Cv would run ya.

Edit* your height measurement is close enough you shouldn't be having a ton of issues from the torsion bars but know that anything over 24.25" causes premature wear. So the higher the number the higher the increase in wear will be.

white89gt

The term they use in that thread is not correct. There is no "auto lock hub" on the gen 10. Every bit of 4WD engagement happens at the differential. AFAIK, that switch is also only used on the manual transfer case, BTW. I think the GEM engages it on the electric cases.


EDIT: Looks like my memory might actually be accurate, lol.....

Jpielert97

I dont know anything about auto hubs. I'm really thinking it is cheap axles. Looking at prices most are like 55$ compared to a new motorcraft which is like 300$. A junkyard shaft is 22$ around me and almost seems worth the gamble. just got to find a truck with an original CV

fordguy2100

Good to know...
sorry I've never actually had to dive into our 4x4 systems (knock on wood). Just saw that after a quick google search sittin in the drive thru lol. Didn't know if the 97 was different since it was the first year

white89gt

Usually.... they will have either a green or a pink sticker wrapped around the shaft. It's usually an easy way to spot them. This is not an F150 shaft, but you can see the Ford sticker on the shaft. It's pink.... just a bit hard to tell because of the flash.