6.9 efficency
Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
Originally Posted by 87crewdually
My last consistant driving in my 87, 6.9, dwcc, c-6, 4.10 R&P truck doing 50-55mph @ 25-2700rpm with 6 cetane boost via Diesel Kleen I got 16.5 mpg. Over drive or 3.55 r&p would help alot more. I don't think thats to bad for a 5000lbs+ truck.
Senior User
Joined: Nov 2007
Posts: 175
Likes: 0
87' E350 6.9 C6 3.31 Srw
The local who does driveline work said he'd install a
3.07 for me for about $300 (used one). It was obvious
doing the calculations and checking mph with a GPS a
3.31 was what was installed.. From 3.55 to 3.31 was
an improvement and a pair of new 33 inch diameter
tirees pretty much got me to where I will stay for awhile.
If I were go to a E40D would a different converter
be needed ? diffferent length driveshaft? other?
Lowell75 thanks.
3.07 for me for about $300 (used one). It was obvious
doing the calculations and checking mph with a GPS a
3.31 was what was installed.. From 3.55 to 3.31 was
an improvement and a pair of new 33 inch diameter
tirees pretty much got me to where I will stay for awhile.
If I were go to a E40D would a different converter
be needed ? diffferent length driveshaft? other?
Lowell75 thanks.
Lead Driver
Joined: Nov 2003
Posts: 6,900
Likes: 3
From: Campbell River, B.C.
Originally Posted by lowell75
The local who does driveline work said he'd install a
3.07 for me for about $300 (used one). It was obvious
doing the calculations and checking mph with a GPS a
3.31 was what was installed.. From 3.55 to 3.31 was
an improvement and a pair of new 33 inch diameter
tirees pretty much got me to where I will stay for awhile.
If I were go to a E40D would a different converter
be needed ? diffferent length driveshaft? other?
Lowell75 thanks.
3.07 for me for about $300 (used one). It was obvious
doing the calculations and checking mph with a GPS a
3.31 was what was installed.. From 3.55 to 3.31 was
an improvement and a pair of new 33 inch diameter
tirees pretty much got me to where I will stay for awhile.
If I were go to a E40D would a different converter
be needed ? diffferent length driveshaft? other?
Lowell75 thanks.
And if you ever want to build up the engine for more power, now is the time to build up the tranny to survive it.
Lead Driver
Joined: Dec 2006
Posts: 6,496
Likes: 94
From: So. Jersey
Originally Posted by David85
16 MPG with a 4.10/C6 combo is very good, just make sure its not an anomalous reading from the fuel shutoff kicking out too soon, I got a 32 MPG reading once (fuel gauge donsn't read accurate, so it looked like it was full). But I think 16 MPG is doable if you consistently cruise at 55 MPH or slightly less. Changing the gears will help bring your optimum cruise speed up slightly, but considereing you are driving the biggest truck possible in that body style, I'd say you are doing well the way it is.
I take no chance with faulty readings from not filling up all the way. Every fill-up I pump it slow at the end til it's in the filler neck for accuracy and longest range.
New User
Joined: Oct 2007
Posts: 2
Likes: 0
The Giant is awake
[QUOTE=xoddah]I just bought a 83 / 84 / 85 ? e-350 cube van 6.9 not run in 3 years
i am - was a cat, cummins, DD diesel tech for a lot of years and have the skills and "some" basic knowledge of automotive diesel with your advise-s posted I'll get'er going my question is with a c-6 transmission what are my options for a "highway" geared differential ...ratios available, and or, possible interchanges with u-pull it wrecking yards ie: will a f-350 diff drop in work in my e-350
this is an additional work van, 400 miles trips don't want the tach pegged all the way there
but for 400$ + make it run costs it is worth a try
WELL I got'er going in about 2 hours absolutely runs like a clock 1986 model almost new
.even has tiger stripe seat covers . a couple of safety issues ( flush brake system) clean out fuel tanks, add a Fuel/Water separator, belts, hoses, fluids, shine it up a little then up and over Mt. Hood for a test ... I live at the bottom so i can roll back home if i have a problem
THEN on to the gear swap
thank you for the great advice
i am - was a cat, cummins, DD diesel tech for a lot of years and have the skills and "some" basic knowledge of automotive diesel with your advise-s posted I'll get'er going my question is with a c-6 transmission what are my options for a "highway" geared differential ...ratios available, and or, possible interchanges with u-pull it wrecking yards ie: will a f-350 diff drop in work in my e-350
this is an additional work van, 400 miles trips don't want the tach pegged all the way there
but for 400$ + make it run costs it is worth a try
WELL I got'er going in about 2 hours absolutely runs like a clock 1986 model almost new
.even has tiger stripe seat covers . a couple of safety issues ( flush brake system) clean out fuel tanks, add a Fuel/Water separator, belts, hoses, fluids, shine it up a little then up and over Mt. Hood for a test ... I live at the bottom so i can roll back home if i have a problem THEN on to the gear swap
thank you for the great advice
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