Buying new v8 or v10 engine help

[Gh0ztkid21]

Originally Posted by boywonder

65mph normal cruising speed.........the trans downshifts on grades....out of overdrive but cruises fine in OD most of the time. On steeper grades it downshifts more than out of OD sometimes.

Many times with the cruise control on I'll turn it off and get the trans to shift back up faster than with the cruise on...slightly annoying..but not really a big deal.....Gives me something to do on the interstate.

When you say driving with OD on are you pulling a trailer or anything? I've never used my over drive button on any vehicle I've owned so I don't know the benifits to using it. I always though it was just for pulling a trailer or something. Please elaborate on its function when cruising and driving normally? What does the over drive actually do?

[boywonder]

Originally Posted by Gh0ztkid21

What does the over drive actually do?

Full Definition of overdrive. 1 : an automotive transmission gear that transmits to the drive shaft a speed greater than engine speed.

That's from Merriam Webster........I think RPM would be better than speed in that definition. Most gear ratios are less than one..ie the engine spins faster than the driveshaft. Overdrive is a gear ratio greater than 1, so the output shaft spins faster than the engine rpm.

When cruising at high speeds overdrive lets the engine spin slower, usually resulting in reduced fuel consumption.

The downshifting I referred to above is with or without a trailer. The only trailer I pull is a tiny motorcycle trailer....

[Gh0ztkid21]

Originally Posted by boywonder

Full Definition of overdrive. 1 : an automotive transmission gear that transmits to the drive shaft a speed greater than engine speed.

That's from Merriam Webster........I think RPM would be better than speed in that definition. Most gear ratios are less than one..ie the engine spins faster than the driveshaft. Overdrive is a gear ratio greater than 1, so the output shaft spins faster than the engine rpm.

When cruising at high speeds overdrive lets the engine spin slower, usually resulting in reduced fuel consumption.

The downshifting I referred to above is with or without a trailer. The only trailer I pull is a tiny motorcycle trailer....

Nice I never knew that. Thank you for that explanation. So when cruising you can turn on the over drive and in turn get better gas milage and put less strain on your engine. (Granted its best on flat surfaces and not in hilly conditions I'm assuming) I always just assumed over drive was for towing. I never knew what it actually was and never tried it.

[carringb]

Pushing the O/D butting actually turns OFF Overdrive (the yellow light actually says OFF). And by default, any time you restart the van it tuns it back on.

The benefit of the O/D OFF button when towing is forcing the transmission to stay in direct drive (3rd in a 4-speed, or 4th in the TorqueShift), instead of trying to use Overdrive, not having enough power to hold speed, then downshifting again. A rig that is at its limits, either too small a motor, or too tall gearing, often can't hold overdrive when towing. I opted to re-gear with lower gears (numerically higher ratio, in my case 3.73-->4.56) which allows me to tow in overdrive. However, that means my engine is always spinning faster so I get worse empty fuel economy than before, but since I can hold Overdrive when towing, I get better towing fuel economy. Plus, better overall hill-climb ability because I can pull steep mountain passes in 2nd, where with stock gears some passes would drop me into 1st! As I side benefit, it puts more torque to the wheels, so it accelerates much faster with and without the trailer, and backs up trailers much better too.

[rallypanam]

Originally Posted by Gh0ztkid21

Nice I never knew that. Thank you for that explanation. So when cruising you can turn on the over drive and in turn get better gas milage and put less strain on your engine. (Granted its best on flat surfaces and not in hilly conditions I'm assuming) I always just assumed over drive was for towing. I never knew what it actually was and never tried it.

You have to turn it off manually, as they are 'on' by default.

[Gh0ztkid21]

Originally Posted by carringb

Pushing the O/D butting actually turns OFF Overdrive (the yellow light actually says OFF). And by default, any time you restart the van it tuns it back on.

The benefit of the O/D OFF button when towing is forcing the transmission to stay in direct drive (3rd in a 4-speed, or 4th in the TorqueShift), instead of trying to use Overdrive, not having enough power to hold speed, then downshifting again. A rig that is at its limits, either too small a motor, or too tall gearing, often can't hold overdrive when towing. I opted to re-gear with lower gears (numerically higher ratio, in my case 3.73-->4.56) which allows me to tow in overdrive. However, that means my engine is always spinning faster so I get worse empty fuel economy than before, but since I can hold Overdrive when towing, I get better towing fuel economy. Plus, better overall hill-climb ability because I can pull steep mountain passes in 2nd, where with stock gears some passes would drop me into 1st! As I side benefit, it puts more torque to the wheels, so it accelerates much faster with and without the trailer, and backs up trailers much better too.

Oh thank you for all that info I never knew that. I've always seen the over drive button but never used it or pushed it so I had no clue about it. Learn something new every day. I appreciate that.

[ctb]

When trying to decide what to order v8 or v10, I went in to one of our local Ford dealers and went back to the shop and talked to a couple mechanics. I basically told them that I would be towing anything, but driving in the mountains, back roads etc...they said that a
v-10 won't have to work as hard but will burn a lot more gas, and a v-8 would work harder, but use less...they said they would rather have an engine that works a little harder more often than a bigger one that doesn't get used as often...one of them said, "That v-8 likes to work hard." So I went with the v-8...I've only had to putt in the slow lane a couple times on a LONG serious grade...but, while fully loaded (water, gear, canoe,stuffnthings)...We average about 13mpg, but we drive her fast to get there...10+ hours to get anywhere away from Iowa i.e.. mountains, Boundrywaters, etc... Good luck in your search!

[chetubi]

My 08 Quadvan 5.4 V8 4x4 with 4.30 gears and 285 70 17 tires and SMB interiour and penthouse top will give me 14 mpg when travelling at 70 mph. But in the city or in mountains it drops to about 11 mpg.
For me the V8 is more than sufficiant.

In germany we tend not to understand those discussions. Here we have sprinter vans carrying big loads with 4-6 cylinders and about 160 horsepower. No commercial van has a V10 or even just a V8. ... And we do have mountains. They Drive the vans with up to 105 mph.

All possible. So this "is a V8 powerful enough" topic is very very US specific i think. (Apart from towing very heavy loads perhaps)

[boywonder]

Originally Posted by chetubi

In germany we tend not to understand those discussions. Here we have sprinter vans carrying big loads with 4-6 cylinders and about 160 horsepower. No commercial van has a V10 or even just a V8. ... And we do have mountains. They Drive the vans with up to 105 mph.

All possible. So this "is a V8 powerful enough" topic is very very US specific i think. (Apart from towing very heavy loads perhaps)

Great point Chetubi! If gas here was $1.50/liter we would be having a different discussion......

[BajaSportsmobile]

Originally Posted by boywonder

.....one test is worth a thousand expert opinions........

Originally Posted by Jsweezy

If the manufacturer is going to lie to me about the MPG of my vehicle right out of the gate then thats ridiculous. I will do an actual test next time I fill up which should be soon and report on the results. Or you could always just tell me how much they lie by and save me the trouble.

Not to belabor the point, but the first thing to do is confirm that your speedometer and odometer are accurate - you can't get an accurate fuel mileage number if the distance you traveled is more or less than you think.

If you do not have a GPS to do this, you can download an App to your Smart Phone.

I check the speedometer of every vehicle I drive... don't want speeding tickets.

My brand new SuperDuty was off by 6 percent from day one. I confirmed this with actual highway mile markers, over 100 miles, on a trip to Utah. And, confirmed it with my GPS speed reading and trip distance.

I put just over 90K miles on that truck and recorded every expense in an Excel Spreadsheet that confirmed, over and over that the trucks computer was reporting false distance traveled and consumption.

It reported that I traveled farther than I had...

I always wondered about the Warranty ramifications - 3 Years / 36,000 Miles could be really 3 Years / 33,840 Miles actually traveled. Add that up over the millions of trucks sold and... someone is lessening their liability.

I'd be interested in you actual results vs. the Lie-O-Meter and actual speed vs. your speedometer.