4.0L SOHC Running Rough

[63falcondude]

I am trying to figure out why my 2000 Explorer has been feeling rough at speed for the past few weeks. I don't have much here to go off of but here it goes anyways...

-Idles smooth
-There is a steady gravel-like feel/vibration that I can feel through the gas pedal and steering wheel most noticeably at speeds > 45-50 mph
-Can't hear anything. I can only feel it.
-Happens all the time (not just in turns).
-No CEL
-Around 157,000 miles
-Can't tell if it is in the engine or something like a wheel bearing going bad (just replaced the front 2 less than a year ago).

Any ideas of what I should look into?

 

[63falcondude]

I am going to check the brakes tomorrow after work. Maybe the brakes are dragging (even though I don't feel any pull to one side or another).

There is also a clunk sometimes when shifting from Drive to Reverse which suggests that I might have a bad U-joint. Can a bad U-joint be causing this rough feeling?

I found this: http://www.doityourself.com/stry/3-signs-of-a-bad-u-joint

 

[63falcondude]

Now I am starting to think that my relatively new (6 months old) hub assembly's might be causing this.

 

[63falcondude]

The hub assemblies were not the problem. Replaced them and still have the roaring noise in the front. Maybe the front differential fluid is all gone??? Is that even plausible?

 

[XLTrunner]

Easy enough to find out. Get under there and remove the fill plug. Stick your finger in there and see if you feel any fluid. Fluid level should be up to the fill hole (truck being level, of course). Check your manual for correct gear lube if need to add.

 

[63falcondude]

Easy enough to find out. Get under there and remove the fill plug. Stick your finger in there and see if you feel any fluid. Fluid level should be up to the fill hole (truck being level, of course). Check your manual for correct gear lube if need to add.

Will do. Thanks for replying! This is driving me nuts.

 

[63falcondude]

Giving in and bringing it to a mechanic. I can hear and feel it now. Very noticeable.

 

[63falcondude]

Mechanic said that it was the driver side hub assembly. He said that it was so obvious he didn't charge me. This was replaced about 8 months ago but maybe I didn't torque it down correctly and that is what caused it to go bad. Should I get a new nut (that goes on the end of the CV joint or reuse the old one?

 

[XLTrunner]

They say to always install a new nut. Local auto parts store should have them. I believe the proper torque is something like 184 ft.lbs. IIRC.

 

[63falcondude]

They say to always install a new nut. Local auto parts store should have them. I believe the proper torque is something like 184 ft.lbs. IIRC.

Thanks. In the manual it said between 156 and 210 I believe, so I went with 170. After replacing the driver side hub assembly the problem is fixed!...for now.

 

[XLTrunner]

Out of curiosity, what brand hub bearings have you been using? They certainly shouldn't be wearing out that quickly...and, I have a hard time believing you damaged them by over-torquing as the recommended max. 210 ft.lbs is about as tight as you can get a nut with normal hand tools.

 

[63falcondude]

Out of curiosity, what brand hub bearings have you been using? They certainly shouldn't be wearing out that quickly...and, I have a hard time believing you damaged them by over-torquing as the recommended max. 210 ft.lbs is about as tight as you can get a nut with normal hand tools.

When my OEM hubs went bad, I replaced them with the cheapest ones that I could find. The brand name is "Detroit Axle".

https://www.amazon.com/gp/product/B009G4Y9RG/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

It is possible that I used my impact to tighten them although I doubt it. I can't imagine not using the 1/2" torque wrench for that but I don't remember to be honest.

 

[XLTrunner]

Quote: "When my OEM hubs went bad, I replaced them with the cheapest ones that I could find. The brand name is 'Detroit Axle' ".

I think you may have found your problem...Detroit Axle. Per their own post on another forum, their bearings are made in China...and, we all know how shoddy the quality is on the majority of products coming out of there. And, bearings are not the place to skimp on quality...even though it's tempting when they are 1/3-1/2 the price of name brands (I know all about different quality of bearings as I was in the business of selling different brands for an Industrial Distributor for many years). Doesn't save you anything in the long run when you're replacing them every 6 mos. Fortunately, you installed them yourself and aren't out the labor by having to pay someone 2 and 3 times over to replace them...for, as you know, warranties don't cover labor.

BTW, I just replaced a RH factory original Timken at 165K miles with another Timken (only brand I use) and was pleased to note on the bearing race itself that they were still being made in the USA.

 

[63falcondude]

The one that I replaced it with is a driveworks (advance auto) so I hope that one will be good. I'm very happy that I have my truck rolling smoothly again!