Hello Mr. Scotty, thank you so much for the years of your instructional and insightful videos and content. It is always tremendously rewarding to see a master work at their craft, whatever profession that may be.
I have two questions sir,
#1, I have this habit of always shifting my transmission into neutral if I’m going down a hill or I am in a situation where I can coast or ‘glide’ to a stop. This habit developed as a conscious effort to maximize fuel economy.
according to the vehicles I have ‘owed’ both of which have been leases a 2020 Santa Fe & Now 2023 Nissan Frontier; the effort has paid dividends. My average fuel economy has increased substantially.
My question is as follows, how much damage I’m I causing to the transmission from the consistent shifting between neutral and drive while the vehicle is in motion. Especially with the Nissan Frontier, I often find myself stalled with the transmission struggling to find the proper gear which seems to come with a jolt one it goes gets into gear. I try to mitigate the jolt by reving at very low rpm’s.
My guess is that the Nissan rear wheel drive has something to do with gear box not grabbing the proper gear into place. Lol but I wish I could understand conceptually what is actually going on. Please offer your insight on this and wether you recommend that I abandone the practice of shifting to neutral for the sake of fuel economy.
#2 My second question is centered on a possible purchase. I would like to purchase a Mercury Grand Marquis’s LS ultimate edition 2005.
It has 116,000 miles on it but they $11,000 for it. The car looks amazing on the outside, and the inside as well. However, I fear that could just be aesthetics.
I know the motor on the car should be good, but how about all of the other internal components, ac, timing belts etc.
My question is what are the components that fail on that vehicle with that kind of mileage, and do you think it’s worth the price.
Thank you very much Mr. Scotty.
Check also some similar questions
https://carkiller.com/scottykilmer/qa/manual-car-question/
https://carkiller.com/scottykilmer/qa/from-neutral-to-drive/
https://carkiller.com/scottykilmer/qa/drifting-your-automatic-in-neutral/
Mr. ofortunato ... Please go read our forum rules. They are right at the top of the main page.
One question per post allowed.
No you absolutely should not "glide" in neutral. First of all, it's against the law. Second you do not save any fuel. Your car is already smart enough to shut off the fuel when it's not needed. Please maintain control of your vehicle at all times sir.
I agree with @mmj, the downside to constantly jiggering with the automatic transmission outweighs the upside. You may get better instantaneous mileage during that one half-mile going downhill, but any long term bump in economy you might get is going to come primarily from just driving sensibly.
Specifically, the problem with being in neutral is that it will delay your response in case you have to make an emergency avoidance maneuver. Also, the transmission is designed to be shifted at rest, not when moving. The best thing is to not try to out-think the engineers; just put it in gear and drive.
Have a great day!
(and, yeah, post #2 in a new thread; you’ll get better answers)
conscious effort to maximize fuel economy.
You may get better instantaneous mileage during that one half-mile
You won't. This is a myth.
First of all, when you take your foot off the accelerator pedal and coast, the engine goes into idle. Same as when you are in neutral. It may not seem that way because the engine is still spinning, but it isn't consuming any more fuel. If you're coasting or going downhill in gear, then the engine cannot stall, so fuel can be shut off completely.
DFCO (deceleration fuel cutoff) is standard in fuel injected vehicles. The PCM detects engine load and accelerator pedal position, and fuel injection is shut off or reduced as necessary. No fuel is consumed until you get on the pedal again. (of course the exact threshold varies with load. You may need additional power for AC, charging, etc)
In fact, a vehicle may even consume MORE fuel in neutral because momentum from the vehicle or gravity are no longer there to drive the crankshaft. In neutral, the computer must supply the engine with enough fuel to keep itself going.
Believe me, if there's any possibly way to improve the economy number on the sticker, car makers will do it.