Quick newbie question on jacking a automatic car

Something came up the mind

Does lifting the rear of a automatic FWD car when it’s in “park” position put stress on the parking prawl? Or is it fine to do so?

.Always set the emergency brake before putting the car into PARK. This will prevent stress on the parking pawl

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He’s asking about jacking up the back end with the tranny in Park.
Yes, it should be in park. It does not put added load on the pawl, because lifting the rear on jacks doesn’t change the angle that gravity is acting on the vehicle, like being on a hill does. The load on the wheels is still straight down, and the load on the parking pawl is as it would be had the rear end not been jacked up.

Bottom line: if the position of the car would not make it roll, it places no added load on the parking pawl. And jacking up the rear end would not make it roll.

As regards the parking brake, it’s pretty hard to work on the rear brakes or rotate the wheels with the parking brake on. :stuck_out_tongue_winking_eye:

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The same amount stress is applied to the parking pawl when the vehicle parked facing down hill.

Setting the parking brake won’t matter. Once the rear tires are lifted off the ground, the parking brake has no effect.

Tester

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Parking brake only applies to the rear.

He needs to block the front wheels then release the e-brake to work on his rear brakes

Right. Shouldn’t really put much stress since when you’re on a hill it’s same or even worse. Haven’t thought of that…

Right. I always chock the opposite I’m lifting.

Anyways my e brake doesn’t really work.

Not if the parking brake isn’t on… and you cannot work on the rear brakes if it is.

The parking pawl has a lot more load on it on a hill without the parking brake compensating for the effects of gravity. That’s why they get stuck and often damaged when people put the vehicle in P on a hill without engaging the parking brake.

Yes, and its very costly to replace! removing a transmission is no fun

When using a floor jack, the lifting pad rotates back while lifting, so lifting can cause pressure on the parking pawl. If the floor jack is placed in a fore-aft position under the vehicle and the wheels of the jack get stuck in the pavement or dirt the front wheels may slide while lifting, this won’t harm the parking pawl, it has more than enough strength for this. Don’t worry about breaking the drivetrain, it can handle a hundred times more force than can be experienced while lifting the vehicle.

Which manufactures have the weak parking pawls that are often damaged? I have performed many transmission repairs but damaged park pawls seem to be an anomaly.

What you’ve implied is not what I said. Stop trying to twist what I write. I did not say that some trannys are more prone to the problem than others. The potential to lock up the parking pawl on a hill, and even damage it trying to release it, applies to all automatic trannys. And no, the floor jack’s slight movement does not put enough load on the pawl to cause damage.

Oh, and a quick search will connect you with countless threads and websites on the subject. It’s a well known problem.
Your apparently being unable to find anything yourself, I’ve taken the liberty of putting a couple of links in to some.


http://m.carcomplaints.com/Chevrolet/Suburban/2001/transmission/power_train-automatic_transmission.shtml

For the record, I’ve never seen a million dollars either… but that doesn’t mean it doesn’t exist.

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In your links there is one report of a parking pawl failure that was posted in 2002.
I guess I misunderstood what you stated; “often damaged”, I though that I must be missing out on all the profit from these repairs however I don’t think anyone is working overtime to repair damaged parking mechanisms.

http://www.binions.com/million_dollar_photo.php

Nevada, if all you want to do is criticize and argue, and that has become clear many times in your posts, than have at it. Have a nice life.

NOTE: trannys left on hills with only the pawl holding them and repeatedly forced out of Park do get damaged. Your taking two words out of a statement just to start an argument is pathetic. Try contributing something useful for a change. You might like it.

Over and out.

Parking pawl damage was a very rare repair for me and the 2 that I do recall resulted from the driver shifting into park while moving. I have seen dozens of cars drug across the pavement and up onto the bed of a roll back wrecker with no damage.

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I think the difference is that the tranny is shifted from Park while not under load. The load on the pawl while it’s being dragged up is static. Were attempts made to shift the tranny out of park while pulling it up on the bed, I think you’d see more damage.

I suspect parking pawl problems may be a much bigger problem in San Francisco than in the “plains states”. Although San Franciscans probably learn to always use the parking brake as a part of learning to drive. Those that don’t probably learn the expensive way. :grin:

I thought the question would concern “car jacking” an automatic car. LOL.

I lived in Duluth for many years. And it was rare that anyone used the parking brake when parking on the hills.

Never heard of anyone having a parking pawl failure. Or having a problem shifting the transmission out of park.

Tester

I only asked you which manufactures have vehicles that are prone to this type of failure. I am familiar with the vehicle lines that I work on, not the common failures of all vehicles. I thought you might be able to explain what you are talking about.

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Have a nice life.