Home Forums Garage Blogs 201 Tips To Save Gas News Reviews Coupons FAQ UserCP Articles
  Mark All Forums Read -  Glossary -  Search The Forums -  View Recent Posts Log Out 

Go Back   GasSavers HomePage > Forums > Fuel Economy > Automatic Transmissions

Automatic Transmissions Discuss how to save on gas for vehicles with automatic transmissions.

Reply
 
Thread Tools Display Modes
Old 07-17-2007, 06:43 PM   #1
rGS
Junior Member
 
Join Date: Jun 2007
Posts: 77
Concerned about my transmission

Ok, so I drove to an errand site and this site doesn't have the FE-style 'H' parking spot in the parking lot but a non-FE-style 'U' parking spot with a curb at the closed end of the 'U'.

So I tried to coast my car into the 'U' shaped parking spot and ended up nudging up against the curb. Since I was at a complete stop, I popped my gear from D to P, then shut off the engine. When I was done with my errand, I hopped into my car, turned on the engine, and when I tried to shift the gear from P to D, there was a somewhat loud "thump" sound. I'm guessing "thump" sounds are not good when it comes to trannies.

So I guess my question is, for future reference, would it be better to change gears from D to N, then from N to P before shutting the engine off? That way, it may release some of the rotational tension that was created due to "nudging against the curb?"
__________________
rGS is offline   Reply With Quote
Old 07-17-2007, 07:01 PM   #2
ELF
Member
 
ELF's Avatar
 
Join Date: Jan 2007
Location: Mpls. MN.
Posts: 293
Quote:
Originally Posted by rGS View Post
Ok,

So I guess my question is, for future reference, would it be better to change gears from D to N, then from N to P before shutting the engine off? That way, it may release some of the rotational tension that was created due to "nudging against the curb?"
Yes, hit N and let the car roll back slightly. Sometimes parking on a steep hill will give the same clunk.
__________________
ELF is offline   Reply With Quote
Old 07-17-2007, 07:03 PM   #3
Gary Palmer
Member
 
Join Date: Mar 2006
Location: Ventura, CA
Posts: 754
I don't think you have anything to worry about. What happens in an Automatic is that when you put the car into park their is a little pawl which moves and engages a tooth on the transmission. This keeps the car from rolling. If you put it into park and then it has pressure on it, like from nudging the curb, parking on a hill and so forth, it makes a thunk sound when it disengages. It is pretty normal.
Gary Palmer is offline   Reply With Quote
Old 07-17-2007, 08:06 PM   #4
GeekGuyAndy
Member
 
GeekGuyAndy's Avatar
 
Join Date: Jul 2007
Location: Oneonta, NY
Posts: 189
I can attest to the hill thump. I use to have a steep driveway and hated that sound. I usually parked elsewhere so avoid that.
__________________
GeekGuyAndy is offline   Reply With Quote
Old 07-31-2007, 08:57 AM   #5
itjstagame
Member
 
Join Date: Jul 2007
Location: Troy, NY
Posts: 289
Quote:
Originally Posted by Gary Palmer View Post
I don't think you have anything to worry about. What happens in an Automatic is that when you put the car into park their is a little pawl which moves and engages a tooth on the transmission. This keeps the car from rolling. If you put it into park and then it has pressure on it, like from nudging the curb, parking on a hill and so forth, it makes a thunk sound when it disengages. It is pretty normal.
Yup, what he said, it's a mechanical sound as the parking 'lock' (if you will) disengages. I've parked slightly up on a curb and had the truck roll back and get even tighter on this lock. It was actaully bound up tight enough I could not get it to disengage (and get out of P). I had to jack up the rear of the truck to relieve the drive train tension.

Oh well lessons learned. But basically either hit N for a second or don't get right up snug to the curb (but either way you can't really hurt anything too bad).
itjstagame is offline   Reply With Quote
Old 07-31-2007, 11:32 AM   #6
Red
For da Llama!
 
Red's Avatar
 
Join Date: Nov 2006
Location: Bay Area, California
Posts: 581
Another trick is to shift into neutral, set your parking brake and let the car rest against the parking brake, then put it into Park. Catch is your parking brake has to be in good condition for this to work well on hills.
__________________
Red is offline   Reply With Quote
Old 08-01-2007, 08:41 AM   #7
Raccoonjoe
Junior Member
 
Join Date: May 2007
Location: NE Indiana
Posts: 101
IMO, you're not going to kill a tranny, unless you do this every day, several times a day, etc.....Something else you might notice: The harder the car is against the tranny (steeper downhill, etc), the harder it is to get the car out of Park.

All you're seeing/feeling is the transmission releasing Park. When the car rolls forward (or backward) like that, its binding up on that gear.....
__________________
Raccoonjoe is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Effect of gear oil viscosity on transmission efficiency (Metroid owners take note) MetroMPG Experiments 20 11-29-2007 03:29 PM
VX Tranny oil Q James Automotive Tech 27 10-15-2007 10:56 PM
Do older Hondas take well to Synthetic what about 0w-20 conventional? jj94auto General Fuel Economy Discussion 12 05-16-2007 10:37 PM
I just finished my HF transmission swap Erik General Fuel Economy Discussion 7 01-30-2007 03:51 PM
Transmission choice for best fuel economy Matt Timion General Fuel Economy Discussion 6 11-09-2005 11:37 AM

Common topics of discusion include: gas mileage, fuel economy, best gas mileage car, MPG, miles per gallon, acetone, increase gas mileage
Archive Links: General Fuel Economy Dicussion - Experiments - General Tech - Automatic Transmissions - Diesels - Aerodynamic Modifications -
How To/Do It Yourself - Articles - Around the House - Electric/Solar Powered - People Powered - Vegetable Oil/Bio-Diesel - Hotel Price Comparison - VPS Hosting - Content Writing - Managed Hosting

 
Copyright 2005-2008 GasSavers.Org