Going to do a test

Reply Subscribe

Thread Tools

Search this Thread

Nov 17, 2007 | 12:21 PM

#16

F350-6

Post Fiend

Joined: Mar 2007

Posts: 26,966

Likes: 50

From: Texas

Quote:

Originally Posted by fixnair

F350, I am always loaded. It is a service truck with a complete set of tool, parts, 200# hoist, air compressor and welder. I think I have 4.11 gears. Anyway 55 MPH is 1750 RPM.

You are right, shifting @ 2000 RPM is hard to do and I find myself instinctivly going higher before I think to shift. I did 125 miles today and the fuel gauge is still at the full mark. I heard a couple of horns too.

You posted back too soon. All the boys with autos were guessing higher and higher mileage, now the guesses are on the way back down.

Unfortunately I think it will take you about 3 tanks to get the feel for the new shift technique where you can do it without thinking. The question is do you have that much patience? Your loaded a little heavier than I was guessing, but as long as your compressor & welder aren't sticking up or out creating excess drag it shouldn't hurt too much.

I guess we'll have our initial results in a few days.

Nov 17, 2007 | 12:27 PM

#17

1996pwrstrk

Cargo Master

Joined: Apr 2004

Posts: 3,162

Likes: 1

From: Vilonia Arkansas

I'm going to say 14. I do 15 driving normal for me hheheh

Nov 21, 2007 | 07:15 PM

#18

fixnair

Thread Starter

Posting Guru

Joined: Sep 2004

Posts: 1,616

Likes: 3

From: Sapulpa OK

Well, I ran the tank down to where the warning light went on and my odometer said 510 miles. I used to only get 400 miles to that point. Filled it up with 33.675 gallons and that calculates to 15.14 MPG.

Quite a difference. Thats about a 25% increase in mileage. It is tough to keep it down especially when everyone is passing you.

I had to take a long trip today, around 250 miles, and I-5 was really busy with everyone getting away for thanksgiving. the only time I got to pass anybody was on my up the grapevine. Got to pass a few trucks but they zommed by me on the way back down the other side.

Want to wish everyone a nice Thanksgiving and I hope you get to spend it with family.

Steve

Nov 21, 2007 | 07:52 PM

#19

F350-6

Post Fiend

Joined: Mar 2007

Posts: 26,966

Likes: 50

From: Texas

25% is a pretty significant increase. Remember to to rev it too high when you down shift. I'm still sticking with my 3 tank theory. I think you'll get up around the 16 range when it's all said and done.

Once you get used to driving at those rpm's try driving an auto and keeping it below 2000 and you'll think your truck is fast.

Nov 22, 2007 | 12:14 AM

#20

fixnair

Thread Starter

Posting Guru

Joined: Sep 2004

Posts: 1,616

Likes: 3

From: Sapulpa OK

Yes! Very significant. At todays prices that should cut my monthly fuel bill from $600.00 to $450.00. Thats a car payment for a Hyundai.

Nov 22, 2007 | 03:24 AM

#21

ernesteugene

Postmaster

Joined: Jun 2006

Posts: 2,647

Likes: 0

From: Fulltime RVer

Quote:

Originally Posted by fixnair

... I think I have 4.11 gears. Anyway 55 MPH is 1750 RPM ....

The DRW has a 4.10 axel ratio, {41 Ring}/{10 Pinion}=4.100, and the 3.73 is {41 Ring}/{11 Pinion}=3.727.

Below is a MPH vs RPM chart for your truck, and the green applies to your 4.10. I also included a 3.73 for comparison, as those with a SRW have that ratio, unless they happened to change it to a 4.10 for better towing like I did.

My chart indicates that 1750 RPM is 55.7 MPH. but if your tire diameter is worn down some, that reduces the MPH a little. Do a careful check at a few of these MPH vs RPM in a couple of different gears, and see how close they come to matching the table.

BTW, I'll be making an overnight stop in Bakersfield on 11/29 (Thurs) at the Orange Grove RV Park, which is on Edison Rd just south of Hwy 58 on the east side of town. Stop by for a beer if you're in the neighborhood! Below is a pic from when we stopped there 3 years ago.

Attached Images

Nov 22, 2007 | 07:28 PM

#22

fixnair

Thread Starter

Posting Guru

Joined: Sep 2004

Posts: 1,616

Likes: 3

From: Sapulpa OK

Went by to see you at 4:45 PM and I guess you hadn't arrived yet. Too bad, I would have liked to meet you. Due to some social obligations I cannot get back this evening. What time are you heading out tomorrow? I have to work but maybe we can meet.

Steve

Nov 22, 2007 | 09:13 PM

#23

ernesteugene

Postmaster

Joined: Jun 2006

Posts: 2,647

Likes: 0

From: Fulltime RVer

Quote:

Originally Posted by ernesteugene

.. BTW, I'll be making an overnight stop in Bakersfield on 11/29 (Thurs) at the Orange Grove RV Park, which is on Edison Rd just south of Hwy 58 on the east side of town. Stop by for a beer if you're in the neighborhood! Below is a pic from when we stopped there 3 years ago...

Well Thurs was the correct DAY, but not the correct WEEK! I'll be there next Thurs, probably by 3 or 4 PM!

Hope you didn't go too far out of your way, and that you can make it next Thurs!