when the truck is dragging- does the truck try to pull in one direction? what did you use to pull the limbs off the trees? and how/where did you hook it to? what is the brake fluid level? when it starts to drag try pulling off to the side of the road and see if you can push the truck on level ground. since its still dragging in neutral then it has nothing to do with the engine, unless you have multiple problems. IMO its a brake system issue or driveline issue. do the brakes drag a little more each time you use them?

 

Glad I read this thread. Have had a similar problem for 12 months or so on a '98 4.6L. Mine was definitely a caliper sticking, but at the time it started there was a noticeable smell (smelled electrical to me), already had the cruise control recall fix done, so I wasn't too worried about a fire (kept it parked away from the house anyway), and no noticeable other problems---so I figured the problem would identify itself further in time. When the squealer on the pads started making noise (at about the normal expected time) I changed them and discovered noticeably more wear on the driver's side than the passenger's. Changed the pads and within 4 months went from bad to worse. The caliper was definitely sticking (truck pulling to one side and rpm's too high to maintain speed)---but only some of the time. Seemed to be much worse when the engine was hot and even when the outside ambient temp was warmer (even remarked to a buddy at work that they never stuck at 5:00 in the morning on the way to work, but at 4:30-5:00 in the afternoon, you could almost count on it). Replaced the caliper and pads again (had the lifetime warranty pads, boy did they get sick of seeing me---sometimes it feels good to stick it to the man). Figured problem solved. No dice---within the last two months it started again (and I've changed the pads again). If you're noticing that type of smell, I'd be highly suspicious of the front brakes. Hard to believe experienced mechanics wouldn't be able to identify the problem, but neither did I. Like I said, there were no noticeable problems associated with it at first---it seems to get progressively worse over time. Anyway, I was planning on flushing that whole brake line this week, but I never suspected the master cylinder. Is it possible that it would bind just one caliper and not the other, or the rear brake drums? The driver's side front is the closest to the MC. Not sure if the modern trucks still use a differential valve, but if memory serves, on the old F150's the valve only separated pressure from back to front---not side to side. The pistons in that one caliper are impossible to force back without loosening the bleeder (on the old one and the new one)--and there's only rear-wheel ABS, so I'm guessing that's not part of the problem. If you take a long drive-at least 20 miles- and it seems like you're having that problem, as soon as you stop stick your nose down around the front wheels and see if there isn't a noticeable difference between the two. Sorry for the long post---food for thought. The Vinman

 

I would agree after rereading your discription it would have to be something with a lot of resistance to make the truck shake. The only logical component would be the brakes. Anything else ( rearend,trany,etc.) would self distruct with that much load causing the truck to react in such a way. Ya, serpentine belt would smell but would be also be toast before the engine would start bucking...

 

You don't need an expensive one of these, they can be found failry cheap, they work for me and can be used for many different diagnostic functions.



Here is one I found at Harbor Freight $29.99

Love that place.

 

When it starts dragging, drive it a bit more, then STOP and get out and FEEL each wheel's hub. If the brakes are sticking, the hub will feel HOT. You don't need a fancy infrared thermometer to do this.

 

If we assume, for a second, that the problem is in the MC wouldn't the symptoms of a hotter than normal hub/disc be present on each side of the vehicle?

 

Idunno, sortuh sounds like a modifier breakdown prob. For the shaking/ washboard description.

The smell could be resulting from shaking loose and burning = Inside the converter or on the exhaust, could be a number of things. I know when they shake from that problem, they shake purdy hard.

I'd have to drive it.

 

The truck does not pull in one direction over another. Feels as though the vehicle is working against an engaged emergency brake. The mechanic seemed to thing the problem was coming from the rear of the turck. When pulling limbs I hooked a tow rope from the limb to the bumper. The brake fluid level is fine but I've never flushed the system.

 

If you don't listen , it ain't gonna get fixed.

Ill give yuh 1200 for it

 

This may be more specific to the vehicle I had at the time.
The brake fluid would heat up, new MC, and not flow back into the reservoir. So, the expansion of the fluid locked the calipers. Once things cooled down, she rolled for a while, and then stopped again. This situation "feels" similar.

 

That's probably true GLC, but that thing is valuable for a lot of different things. My brothers buddy was having problems with his outboard motor (6cyl) missing a little. I loaned him my IRT and he found the problem in no time (coolest cyl). Heck, I even use it to double check temp of stuff I'm cooking or baking. Tool of many uses, I wouldn't want to be without it.

 

Just another guess, but if it has rear drum brakes which I think it does, maybe the limb pulling process caused the truck to readjust the brakes during backup, pull, back up, pull and did something to the rear adjusters that is causing an issue, if the 4 mechanics can't find the problem it's obviously some odd situation.

Even though they spin free on the rack, you might want to ask them to back off on the rear adjustment and see if it helps. Also, the brake shoes dragging may cause the rear Anti-lock to do funning things causing the bucking sensation.

 

i would be suspisous of the drum brakes or the diff.

does your truck have a limited slip diff? ever change the fluid?

 

That's what I thought, but it looks like he doesn't.

Hell with him ..

 

funny how they come asking for help and then they dont listen