Has anyone noticed just as they stop or start a THUNK from somewhere in the suspension or drivetrain?? I thought I read once where there was a TSB to change something to do with the splines on the output shaft of the tranny. Maybe changing the yoke that slides in. I heard of lubing it with something special but that was just a temporary fix. It almost feels like the body slides on the frame a little. What ever it is it's a substantial component thats doing it.

Any help is greatly appreciated---Bob

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99 EB Expedition 5.4L with all the perks,3.73 LS,Heated Mirrors and Seats. Everything but sun-roof. Rhino Step Bar, Ford Bug Shield,More to come...

 

Expybob,

I believe I have the same thing wrong with mine. It feels almost like the axle is wrapping up on mine under acceleration and again on braking. Occasionally I feel it in the steering wheel too on braking.

My truck has low miles, only 27k. I recently bought it used but I know it was not beat, so this is really bothering me too. I haven't taken mine to a dealer yet to get looked at since I have been looking here and for tsb's. Your post was the first I've seen. If you find something out, I would appreciate it if you'd drop me a note, my profile is logged. I plan to have mine looked at by a mechanic friend of mine in a couple weeks. If we find something, I'll post it to you.
Fred

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97 F150 Lariat, Dark Torridor Red/silver, grey leather, extended. Leer running board, deflector, tonneau, bed liner, Superchiped

 

Hi Fred

I took the truck in Monday for other warrenty work and complained of this too. The said they reflashed the computer with new software and it should help. It does seem different now since I think it did it once but it used to do 1 out of two times stopping or starting. They semed to know of the problem. I'll drive it for a while and report back. I would tell the dealer if I were you so if nothing else to get your complaint on paper. My truck is just turning 27000 miles and has been doing this for quite some time. It seemed to get worse over time----Bob

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99 EB Expedition 5.4L with all the perks,3.73 LS,Heated Mirrors and Seats. Everything but sun-roof. Rhino Step Bar, Ford Bug Shield,More to come...

 

I have had my 97 (34,400 miles) back to the Dealer 3 times under warranty for this. Thry keep saying it is dry splines on the rear drive shaft. Had it in in Feb just before warr expired. It was fine untill I drove it in the rain for a couple of days now it is doing it again. Now its my turn to try lubing it I'm going to try some Amsoil Grease I'll let you know!

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97 4x4 sc flareside white
Manik tubes, K&N filter

 

Please do because mine IS still doing it. The software update is not the problem. Somewhere I read on this site thet they ended up changing the yoke that goes into the transfer case on the rear drive shaft to one with an updated spline and that worked. I mentioned this to my dealed and he looked at me like I told him I wanted to trade for a Geo. I believe its the rear axle turning pulling and pushing the yoke in and out of the transfer case.

Thanks---Bob

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99 EB Expedition 5.4L with all the perks,3.73 LS,Heated Mirrors and Seats. Everything but sun-roof. Rhino Step Bar, Ford Bug Shield,More to come...

 

Check under the driver's side of your rear suspension -- look for the bolt which anchors the forward part of your spring to the frame.

I heard thru Latrine-O-gram that this bolt either elongates or is elongated for rear-axle tracking adjustment becomes loose and chucks fore and aft.

Look for a washer and movement tracks on the frame.

Suggestions, reportedly from Ford, include adding a star-washer under the head of the bolt to 'grab' onto the frame -- and another fellow (Lightning forum) has tack-welded the washer to the frame (if this is a tracking adjustment, be sure you're not dog-tracking before you use that method.

Hope this helps (I've never actually Looked under my truck yet -- just remembered this 'fix'.



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Y2K™

XLT SC SB 5.4L 3.73LS

 

P.S.: Let me know if this 'fix' works -- or at least if the root cause includes a loose clamping load on some bolt in that area.

This highlights what I have been trying to pass along to the owner of this board, namely:

If this board were to have a listing of symptoms and then a listing of corrective actions which have addressed those symptoms, this board would truly become a valued user tool.

Merely searching thru myriad snipits of anecdotal data bunched in with other trash-talk is a nice way to spend a rainy evening, but it's not gonna cause anyone to want to buy the web site.

I'm off the topic now, but you get my drift, eh?

Good luck.

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Y2K™

XLT SC SB 5.4L 3.73LS

 

Gents,

I had the same problem on my F250LD 4x4. After stopping at a red light then accelerating, I had a clunk/thud feeling in the drivetrain. I sometimes felt it while slowing to a stop.

I took my truck to the local dealer and he fixed it. They repaced the slip yoke from the transfer case per TSB 97-13-21.

Good luck!

 

I just wrote down the TSB number. I will aslo try to see if there is movement as 7700 suggested. I'll let you know--Thanks, Bob

PS They claimed last time they didn't know anything about the spline.

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99 EB Expedition 5.4L with all the perks,3.73 LS,Heated Mirrors and Seats. Everything but sun-roof. Rhino Step Bar, Ford Bug Shield,More to come...



[This message has been edited by ExpyBob (edited 04-19-2000).]

 

Thanks for the input on this guys. At least I have direction to look. Adding to the possibilities, I saw a buddy of mine this weekend who said he had these same "shifting" symptoms on his 97 f150 also around the mid 20k mile range. He said the dealer replaced a universal under warranty and corrected it. His dealer gave him the impression this was a common problem.



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97 F150 Lariat, Dark Torridor Red/silver, grey leather, extended. Leer running board, deflector, tonneau, bed liner, Superchiped

 

Well, my mechanic buddy just looked at my truck with me and we both agree that my problem is axle wrap-up. We kept our foot on the break and gave it a little gas to watch what was happening. My axle does wrap up a good bit under load and when you let off the gas is relaxes. The axel seemed to rock or kind of pivot on the short, bottom spring. When this happenend, a gap of about 3/4 inch was created beween the bottom and the next spring. Our idea is that if the lower spring was strapped like the two upper ones are, it would prevent this spring seperation and would prevent the axel twist. I'll have to talk to my neighbor who works at a ford dealer. IF I get it corrected, I'll let you all know.
Fred

 

ExpyBob (or) Freds4by,

Any word on this noise! I have the same thing with my 99 F-150 and I only have 11K miles on it. Fred had mentioned the axle wrap, is that what the problem is or is it the driveshaft? I hope someone has some info. I'm affraid to take it to the dealer because a have the lift spindles on the front along with a 3" block and u-bolt in the rear and I'm affraid that would void out my warrenty. Any advise??? Seeing that this seems to be an on going problem with not only F-Series but Expeditions also.

 

I had a thunk when starting-stopping-turning. Checked the spring mounts-lubed slip yolk. No change. Last week, a buddy was following me & when we stopped, he asked if I knew my spare was swinging a couple inches. The take-up was 3/4 turn loose. That fixed my thunk.

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97 Lariet-sc-4.6-4x off road-auto-3.55 LS-
superchip-K&N-Poweraid-3"
pvc air box mod-Granetelli MAF

 

Why is it the easy ones are the hardest to find?

I love happy endings.

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Y2K™

XLT SC SB 5.4L 3.73LS

 

You guys are so lucky, I just ordered the superlift traction bars for the axle wrap thing (they should get here on Thursday or so) but Ihave always had the other thunk sound and I just turned 17000 miles, I think its the slip yoke on this one..Will fix that problem after this one....Good luck, Dave

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1998 F-150, SC/Flairside,oxford white 4x2,4.6,auto,3.55s,nerf bars,cls 111 towing,bed liner w/mat,atlas polished wheels w/285/75 R/16 BFG A/Ts (black side out),all plastics guards/bug shields,air raid/k & n filter, superchipped, duals out the back corners, flow master 3 chamber, snug top lid, f-150 online sticker back window-honk if you see me!!! Fabtech 3 1/2 lift .coverking dash cover, Lumi Logo's (front and rear), clear front corner lenses, muth mirrors,3" bullseye spindles, dash mounted CB, (TX Chapter requirement,lol),personalized license plates.

San Antonio
DWESSELS89@AOL.COM