What you all are describing is a common thing, especially with rear drums. What's happening is the rotors and drum surfaces are rusting overnight. Then, in the am when you hit the brakes at the first stop, it grabs. After that, the rust is cleaned off and braking returns to normal. Try driving a few feet with the brakes on in the morning and seeing if this has any effect on braking.

BTW, not sure about later models, but as far as I know, ABS does not work under a certain speed. 10 mph? Not too sure about the speed or if it's still the case with newer models.

 

I KNOW OF PERSON WHO TURNED IN TRUCK UNDER LEMON LAW IN WASHINGTON STATE FOR JUST THIS PROBLEM. BRAKES ARE SAFTEY PROBLEM AND YES HE GOT A NEW TRUCK

 

I had a 93 Ranger that didn't have ABS and it did that also (in the cold weather and after it had rained). My 97 F150 does it also. A guy at work has a 96 F150 and says it had never happened to him.
Happened the other day with my wife in the truck and about scared her to death! :-) She makes sure to wear her seat belt now! (I was wondering how to get her to wear it)


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'97 F-150, 2WD, 8'bed, 4.2L,5-spd, 3.55 axle, Pendaliner, D. plate toolbox & mud flaps, K&N filter, 3" air box mod,slotted taillight covers, Ventvisors, bug deflector, Westin nerf bars, champion truck plugs, towing pkg, 2000# helper springs, Whelen Responder 2 light bar, 100Watt Street Thunder Siren and speaker, headlight flasher, Rancho RS5000 shocks, Heckethorn 2" leveling kit

 

My 1998 F150 locks the back brakes as well when the weather has been cold and damp. I just learn to live with it as my 1989 and my 1993 Aerostar both did the same thing. They did it with the original Ford brakes and as well after having the brakes redone. I still have the 93 Aerostar with 200,000 KM on it and it just did it the other day when it rained all night.

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98 F150 XLT SC 139" WB 4.6L Automatic 3.55 Rearend Tow Package Toreador Red /Tan 5 Star Lariet Style 16" Wheels 255/70/16 OWL Goodyear AP Tires
Mods K&N Filter, Ranch SportLid Fiberglass Toneau
Tow 22" Terry Taurus

 

well at least i know i'm not alone.first few times mine did it, it scared me to death. way to early in the morning to be sliding to a stop. has been doing it all winter. warm weather it doesn't seem to do it.

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'97 f150 rc, flair side,4x4,v6,5 spd, k&n air filter,

 

I too had this problem, Dealer replaced my shoes with factory replacements. The new shoes have a groove taken out of the centre to allow the linning dust to accumulate away from the drum. Problem solved...... for about 5 weeks. I went back to dealer and they turned my drums. Apparrently the brakes were sticking enough to cause my drums go out of round. True enough the problem is solved. I am very pleaesd about the final out come! I haven't had a problem since.

(Purchased new in June of 99)

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Dennis' comments are the closest thus far.

You're describing a type of 'morning-sickness' where all night the drum brakes have been sitting and taking on moisture and the drums have started to rust. The first (or first couple) of brake applications find the shoe-to-drum contact VERY 'sticky', and resulting in 'brake grab'.

The ABS can do nothing about it for a couple of reasons -- first, you're not stomping on the brakes hard enough for the ABS to sense a hard brake application (thru the hydraulic pressure) - and second, since the brake shoe-to-drum is nearly 'self-energized' at that point, due to the extra 'stickiness' of the contact, the expected brake release by the ABS [if it were to be commanded] would do nothing, since the brake is self-energized -- not locked by excessive hydraulic pressure. So...

...when the tires finally dry and grab (turn) and the brake knocks off the 'sticky' part -- be it goey brake dust and moisture and gritty (rusty) brake drum -- all's well until the next morning where the cycle repeats.

I'll post a bet -- only the trucks that are not garaged exhibit the morning sickness -- since the garaged ones are nice and dry.

Changing brake shoes work for 'fixing' the problem (temporarily) for a few reasons:

a) the new brake shoes don't 'fit' as perfectly into the old drum (especially if the mechanic 'turned' the drum -- which exacerbates the problem of fit),

b) the new shoes are not 'burnished' (cooked) in -- which means that they are not fully ready to do their best, and

c) there is no brake dust floating around to get moist and sticky and 'grout-in' or grab and fill the space between a tightly-mated shoe and drum.

End of Drum Brakes 101.

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XLT SC SB 5.4 4x4 3.73 LS