Newbie with Rear-End question - Ford Powerstroke Diesel Forum
General 6.7 Discussion General 6.7 Discussion

Powerstroke.org is the premier Diesel Truck Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 10-10-2010, 06:42 AM
Member
 

Join Date: Oct 2010
Location: Yucaipa, Ca
Posts: 48
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Newbie with Rear-End question

GREETINGS EVERYONE, I AM VERY NEW TO THE POWERSTROKE GAME…..I HAVE WANTED ONE FOR QUITE SOME TIME AND HAVE FINALLY CONVINCED THE WIFE AND GOT THE GREEEN LIGHT. I WENT FRIDAY NIGHT TO THE LOCAL FORD DEALERSHIP AND WORKED WITH THE FLEET DIRECTOR ON BUILDING THE RIGHT TRUCK FOR MY NEEDS. I WOULD LIKE TO GET SOME IDEAS FROM YOU ALL ON THE AXLE RATIOS, IT WILL BE A CREW CAB 4X4 6.7L AND ALSO MY DAILY DRIVER SO FUEL MILAGE IS IMPORTANT. ALSO IN THE NEAR FUTURE I WOULD LIKE TO GET A 5TH WHEEL TRAILER APPROX 32-36FT WOULD I BE BETTER OFF GOING WITH THE 3.31 OR SHOULD I GET THE 3.55 REAR-END. THEY ARE HOLDING OFF ON THE ORDER TILL I CAN FIGURE THIS OUT….THANK YOU IN ADVANCE
*
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2  
Old 10-10-2010, 08:47 AM
Powerstroke.org Fanatic
 

Join Date: Apr 2010
Location: Gainesvile Florida
Posts: 119
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
get the 3.55 they will be much better for towing that 5th wheel and i dont honestly think you will see that big of a fuel mileage difference between the two when in town driving not towing. but wait for someone that owns a 2011 to chime in to make a decision

best of luck with your choice wish i could afford a 6.7
Reply With Quote Quick reply to this message
  #3  
Old 10-11-2010, 06:53 AM
Compression Ignition Addict
 

Join Date: Aug 2007
Posts: 391
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
3.31 gear with stock 18" wheels/tires @ 70 mph-1500 rpm
3.55 gear with stock 18" wheels/tires @ 70 mph-1900 rpm
3.55 gear with stock 20" wheels/tires @ 70 mph-1700 rpm
IMO...it depens on the size of the wheels/tires you are going with ! As my sig stated...I have 3.55 with 20" wheels,I tow 28ft 5th wheel and a open dirt toys trailer behind that....around 13,000lbs and she's not even breathing hard
Just my .02....good luck
Reply With Quote Quick reply to this message
  #4  
Old 10-11-2010, 09:01 PM
Compression Ignition Addict
 

Join Date: Jan 2008
Posts: 292
Thanks: 0
Thanked 2 Times in 2 Posts
Feedback Score: 0 reviews
Quote:
Originally Posted by ups 6.0 View Post
3.31 gear with stock 18" wheels/tires @ 70 mph-1500 rpm
3.55 gear with stock 18" wheels/tires @ 70 mph-1900 rpm
3.55 gear with stock 20" wheels/tires @ 70 mph-1700 rpm
IMO...it depens on the size of the wheels/tires you are going with ! As my sig stated...I have 3.55 with 20" wheels,I tow 28ft 5th wheel and a open dirt toys trailer behind that....around 13,000lbs and she's not even breathing hard
Just my .02....good luck
The actual RPM numbers look like this though:
3.31 gear with stock 275/70R18 wheels/tires @ 70 mph-1637 rpm (629 Rotations/Mile * 1.16666 Miles/Minute * 3.31 Rear End gear * 0.674 Sixth Gear)
3.55 gear with stock 275/70R18 wheels/tires @ 70 mph-1756 rpm (629 Rotations/Mile * 1.16666 Miles/Minute * 3.55 Rear End gear * 0.674 Sixth Gear)
3.55 gear with stock 275/65R20 wheels/tires @ 70 mph-1689 rpm (605 Rotations/Mile * 1.16666 Miles/Minute * 3.55 Rear End gear * 0.674 Sixth Gear)

Not enough difference between the 3.31&275/70R18 and 3.55&275/65R20 to even worry about, buy whatever suits your style and pocketbook. The factory fit 275/70R18 Conti tyres are notorious POS's though.
Reply With Quote Quick reply to this message
  #5  
Old 10-12-2010, 03:51 AM
Member
 

Join Date: Oct 2010
Location: Yucaipa, Ca
Posts: 48
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Thanks Guys for the feedback, the order was placed yesterday I went with the 3.31's. I guess it's pretty late for special orders per the fleet director and he wasnt even sure if we could still put in for 2011. I guess if Ford accepts it we'll get a confirmation in about 3 days.....I'll keep my fingers crossed!
Reply With Quote Quick reply to this message
  #6  
Old 10-12-2010, 07:10 AM
Compression Ignition Addict
 

Join Date: Jan 2008
Posts: 292
Thanks: 0
Thanked 2 Times in 2 Posts
Feedback Score: 0 reviews
Quote:
Originally Posted by Mason73 View Post
Thanks Guys for the feedback, the order was placed yesterday I went with the 3.31's. I guess it's pretty late for special orders per the fleet director and he wasnt even sure if we could still put in for 2011. I guess if Ford accepts it we'll get a confirmation in about 3 days.....I'll keep my fingers crossed!
Your guy is either confused or ill informed, you still have ~7 months before the 2011 SD cut off:

Quote:
Originally Posted by PowerStrokeHD View Post
Tentative schedule is as follows...

2011 Super Duty

05/06/11 - MY11 Final Orders Due
07/01/11 - MY11 Job Last


2012 Super Duty

03/28/11 - MY12 Order Bank Open
07/11/11 - MY12 Job 1
Reply With Quote Quick reply to this message
  #7  
Old 10-12-2010, 08:26 PM
Compression Ignition Addict
 

Join Date: Apr 2007
Posts: 612
Thanks: 0
Thanked 0 Times in 0 Posts
Feedback Score: 0 reviews
Quote:
Originally Posted by Mason73 View Post
GREETINGS EVERYONE, I AM VERY NEW TO THE POWERSTROKE GAME…..I HAVE WANTED ONE FOR QUITE SOME TIME AND HAVE FINALLY CONVINCED THE WIFE AND GOT THE GREEEN LIGHT. I WENT FRIDAY NIGHT TO THE LOCAL FORD DEALERSHIP AND WORKED WITH THE FLEET DIRECTOR ON BUILDING THE RIGHT TRUCK FOR MY NEEDS. I WOULD LIKE TO GET SOME IDEAS FROM YOU ALL ON THE AXLE RATIOS, IT WILL BE A CREW CAB 4X4 6.7L AND ALSO MY DAILY DRIVER SO FUEL MILAGE IS IMPORTANT. ALSO IN THE NEAR FUTURE I WOULD LIKE TO GET A 5TH WHEEL TRAILER APPROX 32-36FT WOULD I BE BETTER OFF GOING WITH THE 3.31 OR SHOULD I GET THE 3.55 REAR-END. THEY ARE HOLDING OFF ON THE ORDER TILL I CAN FIGURE THIS OUT….THANK YOU IN ADVANCE
*
You picked a good year to convince your wife that you had to decide which rear end was important....my wife kept telling me that we could not afford one. I told her that it might be time to start checking out a new rear end! And you can see what I am driving!!!

Sometimes, they need a little.."perspective".
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Ford Powerstroke Diesel Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -8. The time now is 06:05 AM.


Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.1
Garage Plus, Vendor Tools vBulletin Plugins by Drive Thru Online, Inc.

vB.Sponsors