# Coasting or in-gear: Scenario #2 **URL:** \ **Category:** General Discussion\ **Created:** [December 3, 2009, 3:40am UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293 "2009-12-03T03:40:00Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![kinosh](https://avatars.discourse-cdn.com/v4/letter/k/eada6e/32.png) [@kinosh](https://community.cartalk.com/u/kinosh)\ **Post date:** [December 3, 2009, 3:40am UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/1 "2009-12-03T03:40:00Z")
Lots of debate on moderate hills, but what about very steep hills (12% grade, speed limit of 50 mph) with a stop sign at the bottom? Coasting would be a bad idea, so how would you drive with a 5-speed? Downshift to 4th or even 3rd? ---
**Author:** ![tardis](https://avatars.discourse-cdn.com/v4/letter/t/f0a364/32.png) [@tardis](https://community.cartalk.com/u/tardis)\ **Post date:** [December 3, 2009, 3:43am UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/2 "2009-12-03T03:43:13Z")
Down shift to whatever gear is required to keep your speed down to 50 (or whatever you have decided is safe). ---
**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\ **Post date:** [December 3, 2009, 3:55am UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/3 "2009-12-03T03:55:09Z")
This is the SIMPLE case - listen to Tardis. ---
**Author:** ![oldschool](https://avatars.discourse-cdn.com/v4/letter/o/e19adc/32.png) [@oldschool](https://community.cartalk.com/u/oldschool)\ **Post date:** [December 3, 2009, 5:44am UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/4 "2009-12-03T05:44:07Z")
A big rig driver friend of mine imparted upon me his wisdom about speed control,hills and gear selection. He told me to use the same gear going down as you used going up,can’t say I have driven enough rigs to prove him right or wrong. ---
**Author:** ![FoDaddy](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/fodaddy/32/717_2.png) [@FoDaddy](https://community.cartalk.com/u/FoDaddy)\ **Post date:** [December 3, 2009, 12:46pm UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/5 "2009-12-03T12:46:30Z")
I would use the brakes. ---
**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/30_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\ **Post date:** [December 3, 2009, 2:21pm UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/6 "2009-12-03T14:21:37Z")
Personally, I would downshift to 3rd and use the brakes only as needed. If you rely solely on the brakes, you could wind up with a very nasty surprise when you get to that stop sign at the bottom of the hill. This is particularly true if you don’t change your brake fluid every 3 yrs/30k miles. ---
**Author:** ![Docnick](https://avatars.discourse-cdn.com/v4/letter/d/ecae2f/32.png) [@Docnick](https://community.cartalk.com/u/Docnick)\ **Post date:** [December 3, 2009, 3:04pm UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/7 "2009-12-03T15:04:59Z")
He’s probaly right; with a 5 speed manual that means 3rd gear and with an automatic (4 speed)it would be 3rd or second depending on gear ratio and horsepower. I had a low powered car overseas and for crossing mountain passes, I used 2nd gear on the 3 speed automatic. ---
**Author:** ![dagosa](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/dagosa/32/9837_2.png) [@dagosa](https://community.cartalk.com/u/dagosa)\ **Post date:** [December 3, 2009, 3:47pm UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/8 "2009-12-03T15:47:04Z")
One additional thought, manuals give you an upper limit in rpm’s to down shift, I think it a better idea to anticipate and shift long before your speed has a chance to build up. Easier on the transmission and passengers. I would use the brakes. instead of downshifting makes most sense in really slippery conditions where the abs system can give you better steering control than over braking through the engine. He told me to use the same gear going down as you used going up, I like that advice relative to the trucks and cars I’ve driven with just a few exceptions. A high powered car can easily traverse a hill in a higher gear than you’d want to down shift to in the other direction. ---
**Author:** ![Whitey](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/whitey/32/24680_2.png) [@Whitey](https://community.cartalk.com/u/Whitey)\ **Post date:** [December 3, 2009, 6:49pm UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/9 "2009-12-03T18:49:58Z")
oldschool, that is the old version of the rule. Today’s semis are a little more aerodynamic and efficient. The new version of the rule is to downshift one or two gears, depending on the hill. ---
**Author:** ![tardis](https://avatars.discourse-cdn.com/v4/letter/t/f0a364/32.png) [@tardis](https://community.cartalk.com/u/tardis)\ **Post date:** [December 3, 2009, 7:04pm UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/10 "2009-12-03T19:04:13Z")
If it’s a long hill, you will overheat them and have no braking when you get to the bottom. ---
**Author:** ![FoDaddy](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/fodaddy/32/717_2.png) [@FoDaddy](https://community.cartalk.com/u/FoDaddy)\ **Post date:** [December 3, 2009, 7:28pm UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/11 "2009-12-03T19:28:01Z")
Unlikely in a car made in the last 30 years or so. Maybe in a truck towing a trailer or a loaded truck. But in an ordinary car it’s unusual. ---
**Author:** ![tardis](https://avatars.discourse-cdn.com/v4/letter/t/f0a364/32.png) [@tardis](https://community.cartalk.com/u/tardis)\ **Post date:** [December 3, 2009, 8:01pm UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/12 "2009-12-03T20:01:25Z")
Again, if the hill is long enough, they will overheat. The only question is how long is long enough? In any event, why not downshift and save the brakes? No harm is done to the engine or transmission. ---
**Author:** ![tardis](https://avatars.discourse-cdn.com/v4/letter/t/f0a364/32.png) [@tardis](https://community.cartalk.com/u/tardis)\ **Post date:** [December 3, 2009, 8:02pm UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/13 "2009-12-03T20:02:51Z")
Me too, but now I worry about FoDaddy being behind me. ---
**Author:** ![VDCdriver](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/vdcdriver/32/30_2.png) [@VDCdriver](https://community.cartalk.com/u/VDCdriver)\ **Post date:** [December 3, 2009, 8:57pm UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/14 "2009-12-03T20:57:41Z")
Because of the hygroscopic nature of brake fluid, even if the brake pads hold up in extreme braking, the heat generated can cause the water in old (more than 3 years old) brake fluid to boil. Boiling brake fluid will result in an inability to exert sufficient hydraulic pressure to apply the brakes fully. The result is not pretty. I have been downshifting on hills since I began driving in 1965, and I have never had any instance of automatic transmission failure. Of course, I do change my trans fluid every 3 yrs/30k miles, along with my brake fluid. ---
**Author:** ![waterboy](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/waterboy/32/764_2.png) [@waterboy](https://community.cartalk.com/u/waterboy)\ **Post date:** [December 3, 2009, 11:31pm UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/15 "2009-12-03T23:31:17Z")
Sorry for a stupid related question, after some mountain driving in a rental car enjoying the automatic downshifting via cruise control to control speed, I am thinking there probably is not a cruise control for manual transmissions. I am cheap so my manual trannie vehicles did not even come with electric windows. Is there an option for cruise control with a manual transmission? ---
**Author:** ![FoDaddy](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/fodaddy/32/717_2.png) [@FoDaddy](https://community.cartalk.com/u/FoDaddy)\ **Post date:** [December 3, 2009, 11:41pm UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/16 "2009-12-03T23:41:38Z")
Of course there is. My manual transmission Mustang has cruise control. The transmission type of a vehicle doesn’t dictate the availability of cruise control ---
**Author:** ![FoDaddy](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/fodaddy/32/717_2.png) [@FoDaddy](https://community.cartalk.com/u/FoDaddy)\ **Post date:** [December 3, 2009, 11:44pm UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/17 "2009-12-03T23:44:02Z")
Fear not, my daily driver has fearsome brakes. ---
**Author:** ![kinosh](https://avatars.discourse-cdn.com/v4/letter/k/eada6e/32.png) [@kinosh](https://community.cartalk.com/u/kinosh)\ **Post date:** [December 4, 2009, 12:10am UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/18 "2009-12-04T00:10:40Z")
My Honda Fit could probably hit 5,000-6,000 rpms in 3rd gear going down a steep hill. Would that hurt the engine or transmission? ---
**Author:** ![Whitey](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/whitey/32/24680_2.png) [@Whitey](https://community.cartalk.com/u/Whitey)\ **Post date:** [December 4, 2009, 7:49am UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/19 "2009-12-04T07:49:31Z")
I don’t know where your tachometer’s red line is, but I don’t think it will hurt the engine or the transmission as long as you don’t red-line the engine. ---
**Author:** ![circuitsmith](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/circuitsmith/32/40376_2.png) [@circuitsmith](https://community.cartalk.com/u/circuitsmith)\ **Post date:** [December 4, 2009, 4:13pm UTC](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293/20 "2009-12-04T16:13:26Z")
Every Accord and Civic since '85. [Next page](https://community.cartalk.com/t/coasting-or-in-gear-scenario-2/40293.md?page=2)