idle coasting to a stop

I have a TRD off road quad cab 6 speed manual, when I coast to a stop the RPM is stays around 1400 RPMs. What is with that seems like it doesnt really seem to be good for gas mileage.

 

Learn to downshift.

 

Does it only happen when you first drive? Or all the time?

If it's the former, then your engine just isn't warm enough yet. On cold mornings, my truck will idle at 1500 for a minute or so until it warms up.

Oh, and you should not be coasting to a stop, you should be downshifting.

 

your engine load is actually less when coasting in gear then while in neutral (at a certain point you need to downshift again)

 

I do downshift its within the last few feet before a complete stop. I understand why it would during a cold engine stop, but not when I am getting home from a 20-30 minute drive home from work.

 

Oh, and you should not be coasting to a stop, you should be downshifting.[/QUOTE]

Why should he be downshifting rather than coasting to a stop? If you have to stop, downshifting causes more wear on an expensive clutch than coasting and wearing cheap and easily replaceable brake pads.

 

Why should he be downshifting rather than coasting to a stop? If you have to stop, downshifting causes more wear on an expensive clutch than coasting and wearing cheap and easily replaceable brake pads.[/QUOTE]



DITTO HERE!!
BRAKES are cheaper than a CLUTCH

 

Properly done, downshifting shouldn't cause any more wear and saves on brakes by using the engine. If you're really doing it right, you don't even need to clutch.

The engine remains engaged and in the correct power band in the event you need to accelerate or maneuver.

It saves fuel, because the ECU will let the momentum of the truck drive the engine instead of gasoline by cutting fuel flow when appropriate.

 

It takes the stick V6 time to return to idle that's the way it is, does the same thing if you click off the cruze.

 

What he said!! Its not as safe coasting in neutral to a light or stop sign either. If you needed to get out of the way of something its a lot safer to still be in gear then trying to react and put it in gear

 

I'll disagree with this statement. If the transmission was non-synchroed I would agree ( I drive truck for a living and other than starting and stopping never use the clutch ). But with synchros and a gas engine you will do more harm than good. Most gas engines ( not our 4.0 because it seems to hold RPM as part of it's programming for a bit ) drop off too quickly to make a good matched shift,and you're forcing the synchros causing wear or damage.

 

Correct.

 

i agree with f75 gunslinger,i have over 1.3 million miles safe driving,it is not a peterbilt its a tacoma.

 

This^ unless you are 100% right all the time you are causing the syncros to force the gears to slow or speed up if it gives you even the slightest resistance it's not matched. It far easier to replace a clutch then the syncros and if you don't abuse your clutch you'll get 200K out of it.

 

Firstly, it's much easier to upshift without the clutch than downshift. I would be very surprised if you could go from 5th or 6th gear down to 1st gear, without using the clutch , and have no gear crunching.

Secondly, when downshifting, the engine is nowhere near the proper power band needed for acceleration, unless your downshifting at ungodly high engine speeds.

Thirdly, the amount of fuel you save by having the ECU cut off fuel is well offset by the expensive wear on the trans and clutch disc. Any time the the clutch is used and the flywheel and clutch disc are not PERFECTLY matched in speed, there will be wear.

From a wear and economy standpoint, the optimum way to slow these trucks to a stop is to first anticipate the necessary stop from way back and let off the gas, in gear, as early as possible. Then let the truck decellerate on its own, in gear, with injectors shut off, until you reach a speed at which the engine would lug. Then depress the clutch and gently apply brakes, which should now be minimally necessary.

The way these trucks are programmed to hold the RPMs up when decellerating makes it very difficult to downshift properly in the traditional way. As stated, these trucks are very, very different than a Peterbilt.

 

Well, yeah. It'd be easier yet if there wasn't ~100ms of throttle lag, too.

But, that's why I said if you're "really doing it right"; I was kind of being a smart ass about it. It' s possible, but only really useful theoretically.

Point remains, however, that excessive clutch wear is because of the nut holding the steering wheel.