84 f250 ?

[Tallyho]

My f250 was originally equipped with a 351 but before I got it,  it was swapped with a 460.  Is there items that a stock 460 truck would have that mine doesnt?  Like the radiator,  trans,  gearing ect.  Should i stick to the tow ratings of the 351?
Thanks

[85lebaront2]

Radiator is the same, trans, unless it's a manual that would have been changed too, gearing use your axle ratio and look at the tow ratings in the owner's manual (if you have it).

[Gary Lewis]

Tow ratings are at Specifications/Towing.  And the typical gearing of 3.50 or 3.55 gives 7800 lbs for the 351 and 11,500 for the 460.  But remember that we are talking Gross Combined Weight Rating, and you have to subtract the weight of the truck and its contents from that to get the trailer & its max load.

[Tallyho]

Thanks guys,  it is a manual trans and probably has the trans from the 351.  Is that going to a problem under hard use?
So Gary if I understand you correctly a rough estimate of my actual tow capacity is 11500lbs subtract 5500lbs for the truck leaves 6000lbs?
Then figure 80% of that for safety margin? For a grand total of 4800lbs.

[Gary Lewis]

Yes on the towing capacity.  But, that is just a guess because I don't know your axle ratio.  However, you can figure that out by decoding the certification label.

But no on the transmission.  A 351W has a different bolt pattern for the bell housing than does a 460, so they had to have changed out the transmission with the engine.

[85lebaront2]

Gary, if it is the T18 or any other manual that has a separate clutch housing it could be the same transmission. Bigger concern would be is his the light duty F250 or the heavy duty F250? Rear axle style and wheel bolt pattern will tell on that. If it has the semi-floating axle then it will be the light duty, full floating is the heavy duty (one of Ford's idiosyncrasies of the era) which continued into the late 90s with the new body and mod motored F250 in 98 followed by the Super Duty body so the Power Stroke would fit under the hood.

[Gary Lewis]

Bill - I forgot that some of those have an interchangeable bell housing.  So he could have the 351W transmission but a 460 bell.

However, looking at the towing spec's in the owner's manual Ford didn't seem to think that the specifics of the transmission, meaning 351W T18 or 460 T18, or the model of the truck, meaning F150, 250, or 350, made any difference.  It appears the towing limit was determined by the engine and axle ratio.  Apparently it was just a matter of torque rather than axle, frame, or spring capacity.

[85lebaront2]

Yes, you were thinking ZF5 trannys. The SROD, T18, the old RUG 3 speed, all have a separate clutch housing.

[Gary Lewis]

As does the NP435.

[Tallyho]

All good info guys!  I did a little digging and came up with the info that the 351 had the t18 and the 460 would have had a t19.  T18 had a non synchro 1st granny 6.32:1 ratio to compensate for the lack of power for the 351. While the t18 had a synchronized 1st gear of 4:1 which really isn't a granny low.  
I'm thinking my truck has a t19 because 1st is all but useless for normal driving.  While researching this I could out my reverse ratio is 7.44:1 which makes it incredible slow in reverse while plowing lol.

[Tallyho]

I meant that I believe I have a t18...

[Gary Lewis]

Yes, you should have a T18.

As for the 1st gear ratio, don't believe everything you read on the internet.  I prefer to believe factory documentation, and I have some on this site that says the CA-spec 460's with a T-19 got 5.11 first gears and the 49-state trucks got 6.32 first gears.

Check out the whole of this thread: http://forum.garysgaragemahal.com/No-headaches-6-9-Diesel-td9311i20.html.  Or, go through the Powertrains tab on the 1983 Ford Light Trucks Facts Book.

[Tallyho]

Thanks for that Gary!  Here is a link where I got the info incase your interested.
http://www.novak-adapt.com/knowledge/transmissions/manual/t18-t19
Not that it probably matters but I have a Canadian built truck..

[Gary Lewis]

Yes, if you read that thread that's the site that Jonathan sent me to.  However, it doesn't fit with Ford's publications, so I believe Ford.