Author Topic: Is this bad for my automatic? (Read 1142 times)

aaronk · « **on:** March 08, 2011, 03:48:59 pm »

I drive a car with a manual, my wife has an auto. When I drive her vehicle, which has a gated shifter and a slot for manumatic operation, I often find myself downshifting to engine brake. When approaching a stop light from a distance, instead of simply applying the brake I slide over and downshift - not aggressively, but 'pro'gressively to slow down and reduce brake wear. Here's another one; when I'm at a stop light and I know I'll be there for a while, I shift into neutral so I'm not holding my car back with the brakes and wasting fuel. Is any of this bad for the transmission? I know I'm making the car more efficient, but if I'm ruining my tranny in order to save a few bucks on gas and brake pads it's a losing battle.

johngenx · « **Reply #1 on:** March 08, 2011, 03:59:08 pm »

In the long run, you will cause more wear on the trans doing that. If you're like me and keep cars until 300K or more, it makes a difference. If you trade out every 100K, don't worry about it.

Sir Osis of Liver · « **Reply #2 on:** March 08, 2011, 04:00:16 pm »

Quote from: johngenx on March 08, 2011, 03:59:08 pm

In the long run, you will cause more wear on the trans doing that. If you're like me and keep cars until 300K or more, it makes a difference. If you trade out every 100K, don't worry about it.

mrthompson · « **Reply #3 on:** March 08, 2011, 04:07:20 pm »

New brakes cost less than a new transmission.

tpl · « **Reply #4 on:** March 08, 2011, 04:31:08 pm »

Why would shifting into neutral harm a transmission? and why would gentle downshifting harm it either? If the internal clutches and the gearset in the planetary gearbox can't stand a few '00,000 KMs of that ( with proper maintenance) then perhaps the transmission engineers need to be replaced.

dash · « **Reply #5 on:** March 08, 2011, 04:33:49 pm »

I will shift my transmission into neutral on hot days at long timed lights, assuming that helps it run cooler.

dr_spock · « **Reply #6 on:** March 08, 2011, 05:15:34 pm »

Depending on the car and auto, I used to downshift my auto Sentra. Not sure if it was related, but it left me stranded in Coburg when a washer in the transmission disintegrated clogged up the body valves. It's an auto, let it do its thing.

articsteve · « **Reply #7 on:** March 08, 2011, 05:16:30 pm »

I down shift auto transmissions frequently to brake at 100 kph when I'm hitting a town or when my radar detector goes off. When the detector goes off you never know if the signal is false or not so I automatically jam the tranny down a gear even before I check the speedo or hit the brakes which is the only way the cops can nail you.

Do I think it wears the tranny out? No. Fluid is dumped every 18k km or so. Besides the computer brakes with the tranny as well around town at speed @ 50 to 60 kph just as a function of the OEM set up.

Putting into neutral at lites is pointless.

Schmengie · « **Reply #8 on:** March 08, 2011, 06:52:33 pm »

My brother-in-law's been doing that for ages with no problems at all, and he drives a '99 Grand Caravan with over 200K on it. Really.

mmret · « **Reply #9 on:** March 08, 2011, 09:47:17 pm »

Quote from: articsteve on March 08, 2011, 05:16:30 pm

I down shift auto transmissions frequently to brake at 100 kph when I'm hitting a town or when my radar detector goes off. When the detector goes off you never know if the signal is false or not so I automatically jam the tranny down a gear even before I check the speedo or hit the brakes which is the only way the cops can nail you.

E-brake?

articsteve · « **Reply #10 on:** March 08, 2011, 10:49:44 pm »

On autos like found in a Maxima or Camry or similar unit the E brake is on the floor. Hit that thing at 100 kph and you is a sliding.

In my 944S2 I do pull up on the E brake.

I only got nailed once in the 35 years of using a detector. An OPP was setup on a sweeping blind curve. The tactic is to sit perpendicular to the target car hidden in a wooded rural drive way. As the target vehicle drives by heading into the blind curve the OPP sent out a signal striking the side of the vehicle. Meanwhile, the driver of the target vehicle (me in this case

) assumes that the signal is from an approaching Police vehicle that is coming around the same curve towards them. On go the brake lights and bingo the Police have a dog.

The OPP dude that nailed me had a fairly good sense of humour. He walked up to the vehicle and asked for my license, insurance and radar detector. He waved the speeding fine.

mmret · « **Reply #11 on:** March 08, 2011, 11:05:56 pm »

Two questions:

-I thought the detectors had a fairly narrow arc?
-Don't they use lasers now or something? (pew pew!) Shouldn't those be really hard to detect given the coherency of the beam.

rrocket · « **Reply #12 on:** March 08, 2011, 11:16:24 pm »

Quote from: mmret on March 08, 2011, 11:05:56 pm

Two questions:

-I thought the detectors had a fairly narrow arc?
-Don't they use lasers now or something? (pew pew!) Shouldn't those be really hard to detect given the coherency of the beam.

Laser scramblers work great. Blinder and Laser Star being the best ones. A good thing about the laser scramblers is they are technically legal because they operate on the same rules as laser parking aids and laser cruise control.

Scrambles the laser juuuust long enough for you to slow down, then you click off the jammer.

articsteve · « **Reply #13 on:** March 08, 2011, 11:37:49 pm »

Quote from: mmret on March 08, 2011, 11:05:56 pm

Two questions:

-I thought the detectors had a fairly narrow arc?
-Don't they use lasers now or something? (pew pew!) Shouldn't those be really hard to detect given the coherency of the beam.

Radar detectors have fairly large arc. Lidar or laser have a pin point arc. I'm only defending against moving radar units, not laser guns. Although I passed an OPP standing in the middle of nowhere (hwy 26 east of Owen Sound) this afternoon with a Laser gun. First time I've seen that. Depressing

rrocket · « **Reply #14 on:** March 08, 2011, 11:38:37 pm »

Quote from: articsteve on March 08, 2011, 11:37:49 pm

Quote from: mmret on March 08, 2011, 11:05:56 pm
Two questions:

-I thought the detectors had a fairly narrow arc?
-Don't they use lasers now or something? (pew pew!) Shouldn't those be really hard to detect given the coherency of the beam.

Radar detectors have fairly large arc. Lidar or laser have a pin point arc. I'm only defending against moving radar units, not laser guns. Although I passed an OPP standing in the middle of nowhere (hwy 26 east of Owen Sound) this afternoon with a Laser gun. First time I've seen that. Depressing

See if often out this way. Will have laser scrambler in Supra replacement.

articsteve · « **Reply #15 on:** March 08, 2011, 11:43:45 pm »

The biggest problem with laser is our front license plates. I believe there is a coating available that might help. Regardless, it's a big problem.

rrocket · « **Reply #16 on:** March 08, 2011, 11:49:43 pm »

Quote from: articsteve on March 08, 2011, 11:43:45 pm

The biggest problem with laser is our front license plates. I believe there is a coating available that might help. Regardless, it's a big problem.

As I said, the "laser jammers" they sell are marketed as laser parking aids. So IF you get busted for having it, they can't take it since laser parking aids are legal. Win/win.

articsteve · « **Reply #17 on:** March 08, 2011, 11:58:31 pm »

I will certainly look into it. I thought the big problem was that the vehicle needed 2 "jammers" located on both sides of the vehicle. Like where the fog lights are

Turbo Bob · « **Reply #18 on:** March 09, 2011, 12:00:15 am »

Quote from: aaronk on March 08, 2011, 03:48:59 pm

to slow down and reduce brake wear.

Why would you want to do that, brakes are much cheaper than transmissions.

PJungnitsch · « **Reply #19 on:** March 09, 2011, 12:16:46 am »

I tend to shift down like that, let the engine do some of the work of slowing the vehicle. Especially if traction is poor. Annoys me the way autos tend to 'hang' in high gear otherwise.

Doubt very much it affects the transmission any.