2001 Explorer Bad Vibration

[Joeetogo90]

I have a 2001 XLT with a 4.0 V6 SOHC and it has developed a pretty bad vibration when accelerating. I bought the truck in December of 2016 and the only issues with it were the thermostat being stuck open and the 4X4 lights were flashing. Well I disconnected the battery and got the 4X4 lights to stop flashing and you can hear the transfer case switching from High to Low. Then when I went to replace the thermostat, I had to remove the throttle body and the MAF hose to get to the housing of the thermostat. Once I got that all swapped out and put back together, the truck wouldn't start. I took it apart and put it together a few times and finally I got it to start but it ran rough and would die if it idled too long(it's still kind of sluggish but doesn't really die now unless it's cold). Well anyways after all that happened, my ex. started vibrating when accelerating, sometimes it's noticeable and you can feel it throughout the floor, then some days it's really bad where the dash and seats start rattling and so does the back end. I also noticed with this vibration that the side and sometimes rear view mirror shake so bad that you see the headlights of other vehicles behind me trailing. Everyone that rides with me says they can feel it in the passenger side floor. I initially thought maybe I had a vacuum leak due to the fact I took the MAF hose off or maybe the throttle body position was altered some how when I took it off. I took the truck into my local Sears Automotive since they do free estimates and they barely had it for 10 mins and told me that my rear axle seal is leaking which is causing my rear differential to go bad but they weren't too sure because they don't repair that there. So I don't have a clue what is going on with my ex. It does have the CEL on but the guys at Autozone said it's on because of my gas cap. I find it kind of weird that this vibration started happening after removing the MAF and Throttle Body but just my luck something else could have went wrong. I also thought maybe the 4X4 wasn't disengaging properly since it wasn't working when I got the truck so I disconnected the transfer case motor and it still has the vibration. Any ideas what could be wrong?


Thanks much!

 

[Spuddy]

I have no idea what's going on with your vibration issue, but it's not likely to be anything to do with your transfer case.

 

[Spaznaut]

Is it at a certain speed that the vibration starts? Get worse as you get faster? Ease up on deceleration? You checked your driveshaft u-joints? You may have a knot on a tire. Check for a bulge on the inside sidewall. Check for red residue around the u-joint at the caps.

 

[Joeetogo90]

Is it at a certain speed that the vibration starts? Get worse as you get faster? Ease up on deceleration? You checked your driveshaft u-joints? You may have a knot on a tire. Check for a bulge on the inside sidewall. Check for red residue around the u-joint at the caps.

I took it to Sears Automotive and had my friends husband look at and they both said that the rear axle seal is leaking and the differential is going bad. Do you know if I can just replace the axle seal and not mess with the rear diff? The rear passenger tire is caked with oil/fluid on the inside also everything brake related on that tire is coated in it too. My brakes have been really spongy. It mainly does it from 25mph-50mph real bad then it mellows out, but it causes the side and rear view mirrors to vibrate and sometimes you can feel it in your ears too when it gets real bad. The tires are only 8 months old and were brand new when they were installed. I'm not too familiar with mechanical work, I kind of just wing it or watch youtube videos on how to replace things lol.

 

[XLTrunner]

How exactly do they know the rear diff is going bad? Unless the cover is removed and gears/bearings inspected, it's just speculation. No doubt, if the axle seal has been leaking, the fluid level will be low. That, in itself, doesn't necessarily mean the rear diff is shot, however. Here's where I think you're at with it...the axle seal will need replacing. Only a qualified and trustworthy shop can tell you whether the gears/bearings inside are shot. If so, you're looking at a full rebuild.

My immediate concern would be the spongy brakes you describe. That's a potential safety issue that needs attention asap. Have you been checking/adding brake fluid? Is it possible the oil/fluid on the inside of the rear wheel and brake components is actually brake fluid?

 

[Joeetogo90]

How exactly do they know the rear diff is going bad? Unless the cover is removed and gears/bearings inspected, it's just speculation. No doubt, if the axle seal has been leaking, the fluid level will be low. That, in itself, doesn't necessarily mean the rear diff is shot, however. Here's where I think you're at with it...the axle seal will need replacing. Only a qualified and trustworthy shop can tell you whether the gears/bearings inside are shot. If so, you're looking at a full rebuild.

My immediate concern would be the spongy brakes you describe. That's a potential safety issue that needs attention asap. Have you been checking/adding brake fluid? Is it possible the oil/fluid on the inside of the rear wheel and brake components is actually brake fluid?

I'll take my vehicle to he local ford dealer and have them inspect it. Thanks for the input, I dont know a lot about mechanical stuff so I'm just getting brainwashed with what they are saying lol. I could check the inside of the rim and try and see what type of fluid it is. I got some one me last week when I was looking at it and it smelled like death. So I don't know how either fluids would smell. But you can start to smell it now inside the vehicle. The vibration itself isn't too horrible anymore and it stops when you let off the gas. I parked it today and grabbed my grandparents extra car so it's going to stay parked until I get the ford dealer to look at it. The fluid on the rotor is kind of honey like In color mixed with black and it was just hanging there not dropping off or anything so it's pretty thick. I haven't had to add any brake fluid to it nor has it really seem to have lost much out of the reservoir. I'm trying to take care of this vehicle the best I can. I bought it from a coworker for $1200 with 126,000(now I has 134ish) so I'm hoping to get many more years out of it.

 

[XLTrunner]

Brake fluid is pretty thin...rear diff fluid is thicker than motor oil. Your observations would indicate it is, in fact, diff fluid. It's your choice whether to take it to a Ford dealership...but, I caution you, that's probably the most expensive place you could find to do the work. I had mine rebuilt at a local transmission shop that also does rear axle work. I'm certain it was much cheaper than if I had taken it to a dealership. Actually, any full service repair shop could do this work. Good luck!

 

[Joeetogo90]

Brake fluid is pretty thin...rear diff fluid is thicker than motor oil. Your observations would indicate it is, in fact, diff fluid. It's your choice whether to take it to a Ford dealership...but, I caution you, that's probably the most expensive place you could find to do the work. I had mine rebuilt at a local transmission shop that also does rear axle work. I'm certain it was much cheaper than if I had taken it to a dealership. Actually, any full service repair shop could do this work. Good luck!

I went to a local junk yard and they quoted me at $275 for the part and a friend of mine could put in in for $500. For curiosity sake, I called the local ford dealer and they said I'd be looking at over $1000. They told me they could replace the rear axle seal for $250 and maybe the differential would be okay but they told me I'd have to look at the gears within the differential. I don't know how to go about that, so it has been parked behind my apartment. Might just sell it as-is but it's my only vehicle and I'm currently going through a divorce and filing bankruptcy so I'm kind of screwed with getting a new one.

 

[XLTrunner]

Okay, I think for now you can table the idea of spending $775 for a used rear axle installed by your friend...because at this point, you don't even know if it's necessary. Not to mention, a used axle ass'y could come with it's own hidden issues...unless, you know of someone who is knowledgeable with these things and could inspect everything. Even if the junk yard has a guarantee, I doubt your friend will be willing to do the work a second time for no charge if they offered to replace it. So...what to do next?

I think what I'd do in your situation is take it somewhere with the intention of getting the axle seal replaced. But first, have them remove the diff cover and inspect the gears/bearings before moving forward. If parts are worn, there's really no point in just getting the axle seal replaced. You'll be out the cost of a fluid change if you decide not to have them repair everything...but, at least you'll have some solid information in which to base your next decision as to where to go with it from here. Again, see if you can't find an honest shop that works on transmissions/rear axles/4x4 stuff. If you feel better taking it to a Ford dealership, then so be it. I dug out my receipt from two yrs ago when I had mine rebuilt (including axle seals) and it came to just under $800. Had the work done at my local tranny shop (not a franchise/chain store shop)...who also does this kind of work. Couldn't believe how quiet the rearend became with new parts (Explorers have a reputation for having a howl in the rearend).

 

[imp]

@XL Trunner "(Explorers have a reputation for having a howl in the rearend)."

Often wondered is that has to do with the Aluminum Alloy center section. Rarely in the past did an entire build of given vehicles suffer from rear-axle noise. imp

 

[SWIGIN]

2nd gens don't hve an aluminum center section, so that's something you no longer have to wory about.

 

[imp]

2nd gens don't hve an aluminum center section, so that's something you no longer have to wory about.

@SWIGIN
Good to know that! Unfortunately, I now have a 3rd gen........so that leads me to wonder whether the widespread appearance of gear whine began with 3rd. gens, at least more so than 1st or 2nd.
imp

 

[Joeetogo90]

Okay, I think for now you can table the idea of spending $775 for a used rear axle installed by your friend...because at this point, you don't even know if it's necessary. Not to mention, a used axle ass'y could come with it's own hidden issues...unless, you know of someone who is knowledgeable with these things and could inspect everything. Even if the junk yard has a guarantee, I doubt your friend will be willing to do the work a second time for no charge if they offered to replace it. So...what to do next?

I think what I'd do in your situation is take it somewhere with the intention of getting the axle seal replaced. But first, have them remove the diff cover and inspect the gears/bearings before moving forward. If parts are worn, there's really no point in just getting the axle seal replaced. You'll be out the cost of a fluid change if you decide not to have them repair everything...but, at least you'll have some solid information in which to base your next decision as to where to go with it from here. Again, see if you can't find an honest shop that works on transmissions/rear axles/4x4 stuff. If you feel better taking it to a Ford dealership, then so be it. I dug out my receipt from two yrs ago when I had mine rebuilt (including axle seals) and it came to just under $800. Had the work done at my local tranny shop (not a franchise/chain store shop)...who also does this kind of work. Couldn't believe how quiet the rearend became with new parts (Explorers have a reputation for having a howl in the rearend).

Yeah I definitely plan on avoiding a Ford dealer for sure. I had a coworker offer to do it now for $125 as long as I buy the parts. I was under the truck last night and finally found out I have the 4.10 8.8 Limited slip. If the whole thing with my coworker and/or friend falls through, I'll definitely check out a transmission shop. I haven't been looking around for prices from any shops lately due to my current financial situation but anything beats Ford lol! I can't wait to get it up and running again. I've been driving my grandparents buick lesabre! Miss the exploder!

 

[Joeetogo90]

Well it's been a few months but I figured I'd just post what was going on with my explorer. I had both rear axle seals replaced and the differential looked good, plus rear pads, rotors and calipers replaced. Then about two weeks after that, the front brakes started grinding and eventually got to the point where it locked up the front passenger side tire. I ended up going to Ford for that since it's a block from my apartment. They did the front brakes and told me my rear shackles were bad, so I ended up getting those replaced today. Then I was told that I had a bad U joint when they took it out for a test drive so I had them fix that and my vibration problem is solved finally!!!! It was a U joint this whole time!!!

 

[bigred4x4]

Lol I had a super loud metallic screaming squeaky sound once while accelerating swore up and down I had a torque converter about to fall apart or something serious with the transmission and was all bummed out..... turned out to be just bad u joints.