Hello!
Need some help!
a.I have a 1995 Bronco XLT
b.It has 79,000 miles

Symptons:
a.When I accelerate from a stop.....I feel a clunk or thud coming from underneath.
b.Sometimes when I come to a stop.......same problem.
c.Sometimes when I take my foot off the brake it will clunk also...before accelerating?

I took it to the local Goodyear shop and they did not want to mess with it and did not know what it was?

I called my local Ford Dealer and the service manager said it may be the U-joints or Yoke?

a.Does this sound right?
b.Is it expensive to fix?
c.How long can I go before fixing?
d.Is this a serious problem?

Thanks for any help!
Jeff

 

I had the same problem on my 96 EB. Turned out my driver side shocks were bad. Had the whole lot replaced and the problem went away.

 

My '94 was doing the same thing. "Clunk " when accelerating from a dead stop. Had some silicone grease put on the slip-joint (covered by rubber boot) on rear shaft. Problem disappeared. Any suggestions given are possible, so check them all out.

 

I have the same problem with the 96 (131K miles) that I just bought. I have replaced all of the U-joints and shocks and still have the problem. I have been told that it could be anything from the leaf spring bushings to the rear brakes. So that is where I am going next. Any other suggestions are welcome.

 

My '95 did the same thing until I took out the driveshaft and lubricated the slip yoke. The problem likely is that the slip yoke cannot slip smoothly because there is not enough lubrication. Hope this helps!

 

I replaced the shocks on mine and still have the clunking when i start from a dead stop. Its just like clockwork every time there is 3-4 clunks. Is it the slip yoke. How long will it take to fix?

 

The slip yoke is easy to fix. Chances are you can just disconnect the rear of your driveshaft (make sure the car doesn't role so you align it right when reinstalling) and slide the rubber boot back over the slip joint. Note the orientation of the joint so you can reinstall exactly as it was. Pull the joint apart and clean the splines and regrease them. Slide the joint back together and slide the boot back over it. I was able to use zip-ties to hold the boot in place on mine. Bolt the flange back to the pinion yoke and you should be good to go.
When I did this, it totally eliminated the crunching on acceleration that I was experiencing. If you aren't sure that's the problem, try going over some speed bumps and feel for crunching.
Hope this helps.

 

thanks for the help. I finally got around to to cleaning and regreasing the slip yoke. I could not believe that it was that easy to fix. No telling what the ford dealership would have told me or chanrged me for that matter. No more clunking on take offs.

 

....yeah, i have the same problem....replace virtually everything under there....ball joints, all six shocks, axle joints, radius arm bushings....next is tranny mount...but considering it looks fine....i think it's now the rear driveshaft, or something....and since it has three ujoints on it...and one could be bad...i was told to just replace the whole shaft because eventually i'd be doing the other two, plus the slip joint could be on it's way out....suggestions, thoughts, anyone??.......thanks, paul

 

All you have to do for the (SLIP YOKE FIX) is climb under, disconect the drive shaft from the pinion yoke on the rear end, cut the metal band off the small end of the rubber boot on the drive shaft, then pull the back half of the drive shaft out of the front half, you'll now see the splines, grease up everything very good, slide it back in, slip the rubber boot back in place, sucure the small end of the boot with a big zip tie, now reconect the drive shaft to the rear end. P.S. dont forget to chock the wheeles before you start. should take no more than 30 min. more or less! DW

 

Hi everyone: You would think that with the slip yoke needing lubrication every so often, that Ford would have put a grease fitting there. It isn't like it needs alot. Maybe just a squirt or two.

 

.....just found another problem.....i've been driving around in 4WD, and not realizing it.....damn front shaft is gone!....slip yoke, u-joints...all garbage....and pass side axle is shot, too....also, i'm just going to replace the autos with manuals....warn makes a nice set.....damn truck..... wish me luck y'all......paul

 

At the risk of repeating what two other posts already said quite well ...I am planning on performing this maintenance as well, and here is the Ford workshop version:

---

Slip-Yoke Spline

Vehicle noise and vibration can be caused by a seized driveshaft slip yoke (4841) spline resulting in the rubber isolator being pulled out of the driveshaft center bearing bracket (4A499).

The service resolution to minimize driveshaft slip yoke spline contamination and ultimate seizure is as follows:

1. Disconnect the driveshaft (4602) from the rear axle yoke and remove it from the truck.

2. Clean the male splines of the coupling shaft using care not to damage the plastic coating. Fine abrasive cloth may be required to dress and polish the male spline. Remove all hardened grease deposits, dirt or rust. Inspect for worn or galled splines. The plastic coating on the stub spline must not be removed. Replace coupling shaft if necessary.

3. Clean and inspect the female splines of the driveshaft slip yoke, removing any hardened grease deposits, dirt or rust. Inspect splines for worn or galled conditions, replace driveshaft slip yoke if necessary.

4. Apply a coating of Premium Long-Life Grease XG-1-C or -K or equivalent meeting Ford specification ESA-M1C75-B to the entire splined stub end of the coupling shaft prior to the assembling of the driveshaft to the coupling shaft.

5. Using a clean, long handle (stencil-type) brush apply Premium Long-Life Grease XG-1-C or -K or equivalent meeting Ford specification ESA-M1C75-B spread evenly on all the female splines of the slip yoke. The spline joint must slide freely by hand.

6. Assemble the driveshaft to the coupling shaft with the yokes phased properly. Attach driveshaft to rear axle yoke.

7. Using a hand-type grease gun, lubricate the driveshaft slip yoke through the grease fitting with Premium Long-Life Grease XG-1-C or -K or equivalent meeting Ford specification ESA-M1C75-B.

Part number 7 below is the "female" end that goes to the splined end.

 

hi everyone the solution me and my budies come up with were cheap and easy we drilled and tapped the slipyoke like the older model ford yokes and when i replaced it i used a shock boot to cover splines and four tie straps its lasted a year so far and i can grease it anytime.... shock boot expands with shaft and slip yoke.. hope this helps

 

Looks like the majority of everything is covered. However, let's not forget the radius arm bushings !!! Mine started as a clunking during bumps, and progressed to a thuddding noise. Turns out the urethane bushings installed by ford broke a hole through the radius arm brackets. Not good. I read up and found the urethane is too hard and causes problems with suspension. I replaced the brackets, went back to heavy duty rubber, and I'm a happy camper.