f350 diff ratios
Thread Starter
|
New User
Joined: Jul 2014
Posts: 5
Likes: 0
From: BRISBANE QLD
f350 diff ratios
Im new here so here goes,i have just bought a 1980 F350 beavertail tow truck .It has a dana 60 with 4.56.1 ratio, C6 auto and 351M cleveland on 7.50R16 LT tyres problem is at 100kms it is reving way to high .Do i keep the auto and fit 3.54.1 ratio or put a 5 speed into it it runs on duel fuel unleaded or LPG and does alot of freeway work it used to be a 4 speed and six cylinder and diff is the only original drivetrain left ........
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 787
From: Simi Valley, CA
I'm new here so here goes. I have just bought a 1980 F350 beavertail tow truck. It has a dana 60 
with 4.56.1 ratio, C6 auto and 351M on 7.50R16 LT tyres.
Problem is at 100kms it is revving way too high. Do I keep the auto and fit 3.54.1 ratio, or put a 5 speed into it?
It runs on dual fuel unleaded or LPG and does alot of freeway work, it used to be a 4 speed and six cylinder and diff is the only original drivetrain left.
with 4.56.1 ratio, C6 auto and 351M on 7.50R16 LT tyres.Problem is at 100kms it is revving way too high. Do I keep the auto and fit 3.54.1 ratio, or put a 5 speed into it?
It runs on dual fuel unleaded or LPG and does alot of freeway work, it used to be a 4 speed and six cylinder and diff is the only original drivetrain left.
No 1980 F350 came with a Dana 60. It's either a Dana 61-1 or a Dana 70.
AXLE code printed on the Certification Label, located on the left door face below the latch. Post what it is.
Thread Starter
|
New User
Joined: Jul 2014
Posts: 5
Likes: 0
From: BRISBANE QLD
Diff tag says, 4.56 D9TS
603987-12 also has cast numbers 248
prefix body:AL3JXC 74723C
engine :H
Trans:L
Trim:G
Paint:Y016
Left Plate :S3012
351M :ALIJWY 68138K Cleveland
As far as i can figure out it was a six with 4 speed when it left factory but the ratios dont work at all the poor V8 just revs to high and i would prefer the C6 auto but not sure on what ratio to run or just go to 5 or 6 speed as last resort am planning full restore once my bank account recovers
603987-12 also has cast numbers 248
prefix body:AL3JXC 74723C
engine :H
Trans:L
Trim:G
Paint:Y016
Left Plate :S3012
351M :ALIJWY 68138K Cleveland
As far as i can figure out it was a six with 4 speed when it left factory but the ratios dont work at all the poor V8 just revs to high and i would prefer the C6 auto but not sure on what ratio to run or just go to 5 or 6 speed as last resort am planning full restore once my bank account recovers
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 787
From: Simi Valley, CA
No such Dana rear axle ID tag code for any 1970's or 1980's truck.
What is the AXLE code printed on the Certification Label?
Thru 1980, the engine code is the 4th digit of the 11 digit VIN
H was used 1968/76 (390 2V) & 1977/79 (351M), not in 1980.
There is no L TRANS code for any 1970's/80's truck.
Are you sure this is a 1980? Post the last 6 digits of the 11 digit VIN which will verify the year.
What is the AXLE code printed on the Certification Label?
Thru 1980, the engine code is the 4th digit of the 11 digit VIN
H was used 1968/76 (390 2V) & 1977/79 (351M), not in 1980.
There is no L TRANS code for any 1970's/80's truck.
Are you sure this is a 1980? Post the last 6 digits of the 11 digit VIN which will verify the year.
Thread Starter
|
New User
Joined: Jul 2014
Posts: 5
Likes: 0
From: BRISBANE QLD
Ok thanks ,well i guess i will just play with diff ratios i can get a 3.54.1 will that be ok with the C6 auto or do i need to get lower..if i can get them? dont care about the milage just need to bring down the rev,s so i dont hurt the engine .very rarely do i carry to 4.5 ton gvm only tow custom trikes and small cars or motorcycles but i do travel lots of miles ..
Post Fiend
Joined: Dec 2007
Posts: 8,521
Likes: 16
From: Lost
You post is a little vague in the detail dept. Where are you located? Mentioning speed in kms, and LPG makes me think of Austrailia....
You asked about a 5 speed. If the engine is a 351M, you're pretty much out of luck. Due to the bellhousing bolt pattern of the 351M, there is only one 5 speed trans that will match, and it is far from a direct-fit swap.
But, you referenced it a both a 351M and cleveland. These engines may look the same, at first glance, but they are totally different critters. The 351C saw life from 70-74 in cars for the US market, then got shipped to Austrailia, where it continued to see life well into the 80's, including truck use.
As for the axle, regearing it would be the way to go. But, you need to know what it is, and it looks like ND is on the case. However, if this is an austrailian truck, his books may not have the matching info......
You asked about a 5 speed. If the engine is a 351M, you're pretty much out of luck. Due to the bellhousing bolt pattern of the 351M, there is only one 5 speed trans that will match, and it is far from a direct-fit swap.
But, you referenced it a both a 351M and cleveland. These engines may look the same, at first glance, but they are totally different critters. The 351C saw life from 70-74 in cars for the US market, then got shipped to Austrailia, where it continued to see life well into the 80's, including truck use.
As for the axle, regearing it would be the way to go. But, you need to know what it is, and it looks like ND is on the case. However, if this is an austrailian truck, his books may not have the matching info......
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 787
From: Simi Valley, CA
Sooner or later, you will need to figure out which rear axle this truck has. There are three different 3.54-1 ring & pinions.
Dana 60 takes one type, Dana 61-1 takes another. Dana 70 is different again.
EDIT: OP's "About Me" profile says au .. which I assume is Australia (not Austria). No wonder the codes don't match up.
US VIN's and codes not the same as "Down Under" VIN/codes.
AFAIK, no one FTE can decode ANZAC VIN's and codes.
Dana 60 takes one type, Dana 61-1 takes another. Dana 70 is different again.
EDIT: OP's "About Me" profile says au .. which I assume is Australia (not Austria). No wonder the codes don't match up.
US VIN's and codes not the same as "Down Under" VIN/codes.
AFAIK, no one FTE can decode ANZAC VIN's and codes.
Trending Topics
Thread Starter
|
New User
Joined: Jul 2014
Posts: 5
Likes: 0
From: BRISBANE QLD
compliance plate says 5/80 for year of manufacture. It was built at broadmeadows australia apparantly as a six cylinder ,4 speed ,dual wheels 2x4 .Thats all ford australia could tell me they also ID the dana 60 , made in usa assembled here in australia..
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
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
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 787
From: Simi Valley, CA
Please, when asking further questions, list the country you live in.
I've been pulling my hair out, looking in two different parts catalogs in an effort to figure out what the hell you're working on.
Now I discover it's an Aussie truck.
Look at the upper right corner of this post, this is where you can list Australia.
I've been pulling my hair out, looking in two different parts catalogs in an effort to figure out what the hell you're working on.
Now I discover it's an Aussie truck.
Look at the upper right corner of this post, this is where you can list Australia.
Thread Starter
|
New User
Joined: Jul 2014
Posts: 5
Likes: 0
From: BRISBANE QLD
Rogue wulff sorry about imformation ford australia isnt much help here and its my first time playing with these V8s im use to 302w or 351w so this engine had me stumped because the bellhousing is huge and ford here called it a 351M cleveland it pulls great but just revs way to high .
Thread
Thread Starter
Forum
Replies
Last Post
hickory1991
1973 - 1979 F-100 & Larger F-Series Trucks
11
Feb 17, 2012 12:16 AM
ChaseTruck754
1973 - 1979 F-100 & Larger F-Series Trucks
6
Aug 21, 2007 06:46 PM
sparky69
Clutch, Transmission, Differential, Axle & Transfer Case
8
Dec 21, 2005 07:25 PM
78f250RangerExplorer
1973 - 1979 F-100 & Larger F-Series Trucks
4
Aug 1, 2004 11:31 AM