Why don't you say what EXACTLY is going on. Your jumping back and forth between coils and rear end. I explained both in detail.

What's simply the problem, be as short as possible. If there's two then state both. That may help others help you since they're most likley going by the first page before skipping to the rear.

Because if it's just and you can't distinguish between a rear end or drive line without the engine as a separate, then you should give up and take it in before more problems come of it. I've read the thread a few times and I get the impression you don't know, even now.

Trying to help, but your jumping around from one spot to the other

 

Hell, I might thro in the towel...

 

You say a shudder in the title. A shudder in the drive-line from a straight is a Torque converter problem most likley. Not locking properly.

You know, something simple and go from there.

 

When i take off form dead stop, going forward, at full throttle, the tires brake lose, then hesitates(shudder) for maybe a second, after that its fine.

I have also noticed that going 45mph i feel a small bump almost like some is out of balance, but only at 45. i play with the gas at this speed pushing it and letting off when i let off, it feels as either a slight miss, or the rear is hoping.

Also when i take off form a dead stop, full throttle, turning left or right, its fine, it doesnt hesitate or shudder.

When i slowly push the throttle at take off, dont matter which way im headed, then floor it after its rolling, IT WORKS FINE.

At the time the problem started happening i was unsure if it was motor related, trans, rear. I wasnt sure if it was some sort of misfire, fuel related, trans, u-joint, slip joint, rear end.

So far everything i have done only made the truck run better, It HAS NOT fixed my problem. I might be picky over just a small thing that doesnt matter. BUT this problem started about a month ago, BEFORE that it has never done anything close to this.

So far to bring everyone up to speed as what i have tired to fix the issue: Spark plugs changed, fuel system cleaned, coils changed, trans fluid changed, rear end checked, u-joints checked, slip joint re-greased, switched tires. Only Things i have yet to do, for the simple reason to cross them of the list, as being tried is: fuel filter, adding more modifier. And i have a feeling those are not going to do nothing either.

Everything Runs fine the way its suppose to other then the above issue at floor throttle take off. Nothing performance wise was changed since 2010.

Someone mentioned i was sucking in to much air, or something with the superchips tune, To sum I havent added/removed any parts since 2009 How it was then is how it is now. And just randomly this problem starts one day, and i cant find out what it is, and no one else i talked to in person can either.

It is bugging the crap out me because i dont know whats causing this, when everything i have done or checked is fine or doesnt fix it.

Hopefully this clears up everything. Sorry for going back and forth, but i would read one thing and think it was that and another person said that, so i was just doing it all the rule everything out.

 

Alright, alright, what a PITA.

So have you returned the vehicle to the factory settings ? The way it was originally. Sometimes these tunes get buggy, just happens and can happen at any time.

What happens then AFTER loading the factory program ?

BTW, thanks for parsing those paragraphs; it's easier. For me anyway.

 

Yes I have put it back to stock. and only noticed the hp loss and the throttle lag. normal. but it still did the shudder/hesitate.

The hesitate/shudder take off straight does it also in 2nd gear, and overdrive on/off it dont matter.

I thought i would try and make it simple for everyone to understand my issues, at one time i was beginning to thank i had more then two problems. I still might. Thanks for your help.

 

Alright. Taking off normally, - under NORMAL acceleration, at around 45mph, just after the shift into OVERdrive, -how does it run at this particular load. Right after the shift, very important. It could be 50 mph depending on the tune.

It's at this EXACT engine load a coil will act up. So if you have a low grade misfire or any coil problem what so ever, it's at this point in shift/load where it will be at it's worst.

That is how you can cut to the chase, if it's a coil.

 

Really this is interesting to know. Under what i would call normal/slight take off at a lower rpm maybe a max of 2000rpm the truck is fine. When i keep this same rpm level up to 40mph which is when o/d kicks in, it to me seems to be running fine.

The thing i feel at 45 I will try to discribe better. It feels to me like when im going a hair over 45 and let off the gas it feel like the rear end is real springy, and when i hit the gas and get the rpm and speed, feel like this springy feeling along with something slipping in and out. Which my first thought was overdrive, which i already ruled that out.

Off topic nothing to do with coils: My buddy who has 7 years of tire, balance, alginment, exp. rode with me today. He in fact felt the same thing so im not losing my mind, he seemed to think it was axle wrap. So while he was over he wanted to do some testing.

I put it in gear and power braked it as he watched the leaf spring. We switched places i saw the the front half of leaf spring didnt move. But the back half went down. We both thought if it was axle wrap the the front would be going up and the rear down. Only the back is going down, as well as the whole truck body. Im not sure if this is normal for just the back to drop, or is a problem. My axle is on top of leafs (flipped/lowered)

This was his guess was axle wrap, not saying it is just saying what other stuff i found out today. not trying to confuse you again.

 

Rear Axle: -Hard to say on the axle wrap. It's going in the right direction, it depends how much. You can correct that with a Hotchkiss kit. IF you need one, they're. I'd use one for axle wrap now, if I was still pulling allot of weight with the 98. I had to reline the axle, drop the springs, replace all the pads in between them at one time. Just backing a trailer with a full size van on board up hill and an s drive to boot. So if you've do any of that.....

Also:

If you hauled heavy or to much weight and broke the arch from it's original bend. Then yes, you stretched the metal and weakened it. Sometimes you can tell from looking at the spring sides for broken and cracked paint.
__________________________________________________ ____________

The other problem, I'd have to drive it. It could be the drive by wire system as well. = Throttle body motor.

 

i dont haul or pull nothing. i maybe at one time had 500lbs max in the bed, and i pulled a 91 toyota home maybe 1mile, but this was over 2 years ago. the 500lbs was maybe 9 months ago, and that wasnt for a total of 5-6miles. Oh almost forgot like this would hurt it i pulled a small 4x8 single axle lawn trailer with a lawn mover on it for a 20mile trip and empty the 20miles back. Truck has never seen nothing that heavy.

Going over board here to really solve this problem, just put a whole new rear end in it, springs, axle, ect. that should fix it right


The other issue, this shows you how smart the guys at autozone are, he said the IAC valve might be bad, egr, pcv, or tps. Well im not real sure but i dont think my truck has an IAC, and im real sure that my pcv doesnt cost $3.

Unless the issues are somehow related to something all of us are overlooking. I just dont know.

My buddy who own the exhaust shop, also doesnt lifts on trucks, builds mud buggies, and drag cars, im sure he can fix me up with a some sort of tracion bars. I was thinking of something like a ladder bar, but do that with only one bar going form axle to frame. In between of a ladder and 4-link. Not sure if i have sold myself to be the problem with the rear axle.

 

Yea, hard to say where the problem is I guess. UNCLE

Ladder bars Yea, you could do a 4 link

I would do anything like that tho. Not unless I was at 500 hp. I'd go cheap with a bolt on Hotchkiss. All you need. That's done all the time, - IF! -Your worried about wrap.

 

Yeah ill try and get this we'll it "wrap problem" done first, at least i have a good place to start instead of just wondering if its one part or the other which i think what going to happen with the "45 problem"

The Hotchkiss kit i cant find nothing for my year, actually i have looked all over the place for 4-link, ladder bar, and cant find any for my year. I found some stuff for 4wd but nothing for 2wd.

Is this a universal kit your speaking of?

just to be sure we are talking about the samething, you are talking about a square tube that bolts to the leaf springs?

The thing that gets me most is this problem just randomly started one day....both of them for that matter?????

 

Yea, Mitch has one and a pick of it. Only one I can find right now.

https://www.f150online.com/forums/me...998-23167.html

Mitch is still active, you can PM him a message, just tell him I told you to or something so he'll answer yuh. You can PM him here -

https://www.f150online.com/forums/pr...=newpm&u=11302

 

alright still one other problem, the one in the picture will not work for mine. What you see in the picture flip over every thing and you have what mine looks like. My axle is actually sitting on top of the leafs. The way it was lowered, was the spring perch was cut off the top using a plasma cutter then welded back to the bottom of the axle, and the leaf pack hardware was flipped(not the spring itself)

Just in case anyone asks: Everything was lined back up before it was welded back. This was done feb 2009. So if a problem happened to be because of the way it was done, im sure i would have noticed it by now.

The only problem since it was lowered with the use of a "kit" I highly doubt im going to find a kit to work. Its prolly going to have to be custom.

I'll get my zip ties, superglue, and duct tape out and fix it

I will PM him and see what he has to say.

 

I think this is what might work better for st one50's situation... If he is having an axle wrap situation..



What I have is for more payload in the bed with less sagging.. Yes, it did help my axle wrap issues as a side benefit, but the major reason for them is to be able to overload my truck!

Mitch