6.9vs7.3 mpg
Thread Starter
|
Senior User
Joined: Sep 2007
Posts: 132
Likes: 0
6.9vs7.3 mpg
Which gets better gas mileage, the 6.9 or the 7.3? stock that is. I want to know because I'm looking at buying a f-2or350 with a diesel engine, but I don't have enough money to buy a newer one. So I'm looking at the 80s and early 90s, and I would like to know which one gets better mileage and performs better?
Brett
Brett
Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
Generally, the 7.3 will get better MPG if for no other reason than that fact that they were nearly all equipped with overdrive transmissions (except for 1988 and special ordered trucks that used the older transmissions). The prechamber design was sightly revised on the 7.3 compared to the 6.9 for emissions reasons, not sure if that would affect MPGs (doubt it).
20 MPG is doable with the right conditions and powertrain configuration.
20 MPG is doable with the right conditions and powertrain configuration.
Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
Originally Posted by evictorwalli
She has a 5 speed manual trans...
Most of the folks that post numbers of 20 MPGs have 7.3 powered trucks with 5 speeds. Not that its not possible with a 6.9, just not as likely since its so rare to get one with a overdrive tranny.
Postmaster
Joined: Dec 2002
Posts: 3,594
Likes: 2
From: Southern Oregon USA
Trending Topics
Senior User
Joined: Sep 2007
Posts: 113
Likes: 0
From: Ninilchik, Alaska
Not sure about the gearing. I'll see if I can find out when I get home next week. No idea on how to check besides pulling the rear diff. cover off and counting. Any way to tell off hand? Form memory I think I'm turning right at 2000 rpm at 65 mph on 235 85R16. Is there a online calculator to figure it out?
To answer Brett's question though what milage are you all seeing?
Oh and the winter diesel gets much worse milage haven't figured it out yet but I think it'll be about 16.5-17 mpg.
To answer Brett's question though what milage are you all seeing?
Oh and the winter diesel gets much worse milage haven't figured it out yet but I think it'll be about 16.5-17 mpg.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 6 Best Deals Available on New Fords & Lincolns Right Now
Brett Foote
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Verdad Gallardo
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Laughing Gas
Joined: Aug 2007
Posts: 1,132
Likes: 0
From: Baldwin, ND
Originally Posted by evictorwalli
Not sure about the gearing. I'll see if I can find out when I get home next week. No idea on how to check besides pulling the rear diff. cover off and counting. Any way to tell off hand? Form memory I think I'm turning right at 2000 rpm at 65 mph on 235 85R16. Is there a online calculator to figure it out?
http://www.accuautoparts.com/calculatorfin.jsp\
Hope that helps
Thad
Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
The stock setting of the IP is pretty good for overall performance, but turning the fuel down probably won't hurt anything. It might be a little harder to start when cold though.
If the auto tranny is a factory original, it would be a C6 3 speed for 2wd or 4wd.
If the auto tranny is a factory original, it would be a C6 3 speed for 2wd or 4wd.
Thread
Thread Starter
Forum
Replies
Last Post
brettdacosta
1973 - 1979 F-100 & Larger F-Series Trucks
8
Jan 8, 2016 10:13 AM
Edgethis
1967 - 1972 F-100 & Larger F-Series Trucks
7
Oct 10, 2015 09:56 AM
TylerLaFountaine
Pre-Power Stroke Diesel (7.3L IDI & 6.9L)
1
Dec 16, 2014 01:55 PM