F150 rolls when in park


#1

The other day I put my truck in park and it started to slowly roll, and while it did made a clicking noise from underneath, till it finally caught and stopped. About the same time, it would only start if I put the selector on N. This problem is not every time I start it maybe 30% of the time. It had been a few days since the rolling in park incident, but today I put the truck in part, it started rolling, again making a grinding noise, but it never stopped rolling. Had to use the E brake to get it to stay in place. On my drive home I turned the radio off and everything sounds good when shifting gears. If I have to start the truck with the selector in N no big deal, if I have to start using the E brake no big deal. But is this the start of some bigger transmission problem? My knowledge of vehicles only allows me to check the transmission fluid, and it was within the cross hatched lines.
Truck is a 98 F-150, 6 cylinder, 60K miles. Not sure if I want to start putting large sums of money in this thing or consider an upgrade.

Thanks for any help or advice anyone can give.
Ben H


#2

You want to check if the shift cable is operating correctly.

https://www.rockauto.com/en/moreinfo.php?pk=2950068&cc=1315003&jsn=450

Because when you operate the shifter, the shift cable is what positions the shift lever on the transmission, and the park/neutral safety switch below the shift lever on the transmission.

Tester


#3

Thank you,
I do HVAC for a living so my mechanical aptitude is there just know nothing about cars. That being said, is this something I would be able to check, or just take this to a shop? Would this issue relate to both of my symptoms?

Thank you for the link and start of research.
Ben


#4

Sure!

You can check the shift cable/lever/park/neutral safety switch yourself.

Crawl under the left side of the truck where the shift lever is on the transmission.

Have someone turn the ignition switch to on so the dash lights come on, and then step on the brake pedal. Now have them operate the shifter so you can watch the transmission shift thru its ranges.

Now have the person put the transmission in park and shut the ignition off.

Now reach up and see if the transmission lever can be moved to one more position.

If it can, there’s a problem with the shift cable.

Tester


#5

You probably already know this OP, but an automatic transmission has a part called the parking prawl pawl. The purpose of that part is to prevent the truck from moving when the transmission is in Park. I’m not exactly sure what happens inside the transmission, but somehow the prawl engages with some gear or something and that prevents the driven wheels from turning.

Those prawls pawls can break right off, so that’s one possibility. That can happen if say you try to engage Park with the truck still moving. Even if the prawl is not broken, it can fail to engage b/c the transmission selector isn’t quite making it to the right position.

Editted to accommodate spelling error noted below. FYI

Def’n of “prawl” according to the Urban Dictionary

A word used by some North Carolinians to describe seeking booty throughout the course of a night of drinking. Can also be used as a term of endearment for Delta Upsilon’s sweetheart.
Def’n of “pawl” according to the Google dictionary

A pivoted curved bar or lever whose free end engages with the teeth of a cogwheel or ratchet so that the wheel or ratchet can only turn or move one way.


#6

It’s a ‘pawl’.


#7

I am sure Texases is correct. But, Prawl does sound like something delicious from the ocean.


#8

This all sounds like it more than I really care to deal with. Have a friend that is an old diesel mechanic. Problem with him he is reaching 70 years old. I might call him with what you guys said and see what he says. I have no problem ripping into a furnace or a/c, but this is all uncharted territory for me. Most likely will leave it to you guys in the field. Ill give this old man a call and see if he will look at it.

Thanks everyone.
Ben


#9

A few ideas:


#10

hmm. hmm. f it. give me a screwdriver and ill see what i can do lol. I don’t envy people that crawl around in peoples cars like this for a living. But my pointer is off too. Least of my worries at this point. Thanks for this video.
Ben


#11

My pointer isn’t work that well either … lol …


#12

By the way, you’re supposed to use your parking brake when parking. This situation is exactly why that’s a good idea.


#13

Lion9car, I am sure that is the case (never heard it before), but in reality, how many people actually apply this practice? In all my years of being in cars, I dont think I have ever seen anyone do this on an automatic tranny. Even when I would drive a standard, I seldom used the E brake. Just threw it in a gear and went about my day. Right or wrong, its pretty much how I was brought up, so its what I did.


#14
"in reality, how many people actually apply this practice?"

I guess that we travel in very different circles, as everyone with whom I drive is in the camp that uses the e-brake + the transmission’s “park” function when they park their cars. The only time that I don’t use the e-brake in this manner is when parking the car during very cold and wet conditions, as I don’t want the brake cable to freeze to the underside of the chassis.


#15

I agree with Ben. I always left it in first (MT) or park (AT) unless parked on a significant slope, where I did use the parking brake. Still do.

Possibly living in a salt area, we were trying to save the parking brake cable from rusting out, a common occurrence then.


#16

The proper parking technique is to apply the parking brake (OP calls it the E brake) and then put the tranny into park. This reduces the stress on the pawl in the tranny which is substantial if you park on a slope.

My brother broke the transmission case on a '61 Mercury lot’s of years ago (car was 3 years old at the time). The pawl is supposed to break, but in this case it sheared off the raised area on the transmission case that it hooks onto. It was a expensive lesson for him and showed me that an abusing “park” in an auto transmission could break stuff internally.

I don’t think of the parking brake as an E brake. Most newer cars have 4 wheel disk brakes. The small brake shoes in the mini rear brake drums in this set up has virtually no braking power. In an emergency those tiny drums overheat so fast that the car isn’t going to stop from 60 mph much faster than if it simply coasted to a stop.

The rear drums in the OP’s old truck would do a much better job in an emergency. But if you have 4 wheel disk brakes don’t expect much braking in an emergency.


#17

Im going to start calling around to see what prices im looking at to have the bottom cover taken off, and hopefully have this pawl removed or repaired, then have new fluid. This was suggested to me by someone. they also said, sure better hope its accessible from the bottom. FML.


#18

Me, I’ve always done what Uncle Turbo suggests above, set the parking brake first, then Park if an automatic or 1st gear if manual. I figure if something breaks in the process, its cheaper to fix the parking brake than the transmission.


#19

Did the person who suggested the park pawl repair inspect the shift cable? This sounds like a simple cable problem, the grommets on the cable ends fail and the cable becomes loose.


#20

The video that was posted on here (not sure how to copy it) was the issue. The little plastic adjustment piece is broke, which im assuming has been for a while since it always said I was in 2 when actually in D. Not a big issue for me, one spot is R and 2 more is D, I can handle that. But whatever that metal plate does, the screws were loose on it like in the video. But I felt mine were much worse then his. I tightened those up really good and then tested it out on a very small incline. She stayed put. A friend who teaches automotive but cant take vehicles to the school to work on said the plastic cable adjustment is only to line the pointer up and wont cause any issues, just might be annoying that it says 2 instead of D, is that a fair statement?

Thanks again to the person who posted the video, saved me a bunch of money. But now I am curious, what is that little metal plate do. Could not see what it went to, and I dont know much about cars other than to change the oil.

Thanks
Ben