howmuch upgrade due to a c4?

[ford6t5]

hello, i want to swap my three speed manual for a c4 auto transmission. do i get lower rpm's at higher speed? (or will this be the same). if not what is the best and cheapest way to get lower rpm's at higher speed. truck has the original three on the tree.('65 f100) and makes to much rpm's at higher speed. it has the good 300 cui L6 . it has also the original rear axle and i do not know thw ratio.

see ya

twan

[banjopicker66]

Unless you install an overdrive transmission, either an automatic or a manual one, the output is still the same. You get no advantage changing transmissions unless it is an overdrive.

The easiest and best way (in my opinion) is to change the rear axle ratio.

If you have a Ford 9" rear, it is easy to do, and one person can do it in about an hour, or less.
To check if you have a Ford 9" rear, look under the truck.
If the front of the axle has 13 nuts, it is a Ford 9". It will not have a removable rear cover.

The other type axle will have bolts in the rear, and a removable cover.

The first best thing to do is determine what you have in there now.

[BarnieTrk]

Twan,

I suggest you first determine what rear gear ratio you have.
Go here to figure out how to determine your ratio: http://fordtruk.com/forums/viewtopic.php?t=23231

Then come back here and tell us what ratio you determined and if it's a 9" rear differential housing or not.

BarnieTrk

[ford6t5]

yes i will do that but it takes some time..

thanks so far for your input.

see ya

twan

[Leeroy]

I just went through this myself (axle ratio that is) Mine was a 3.89 posi that I changed to a 3.5 (just changed the gearset) I run 17" wheels which gives a tyre size of 28.9" Knocked just under 300rpm off at 60mph.

[BarnieTrk]

Say Leeroy,
Since you reduced your cruising rpms by 300 @ 60mph, how has it affected your fuel mileage?

I'm assuming your mileage has improved some, I am just wondering how much it has improved........

Thanks!
BarnieTrk

[ford6t5]

well things have changed, i came across a aod transmission. not so much laying around here in holland. the guy say's it comes out off a '85-'86 mustang 302 v8.
so now my question is:

will it fit to my 300 L6?

if so i do not have to change my rear axle and i was going to change the manual to a c4 so that would be the same..

where to look for? trans is out off the car and laid for a couple off years.

see ya

twan

[jamesdfo]

Twan: If possible, see if the seller still has the TV cable (Throttle Valve). The AOD's use a cable instead of a kickdown linkage like you would find on a C4/C6, and if not installed or set up properly , the trans will not last for long. If the original TV cable is not available, I believe aftermarket ones are available from LOKAR and possibly others.

James

[bruceandersson]

I put a 4 spd OD unit from a mid-80's pickup into my short bed. The front splines and bolt patterns are the same. You might have to have your drive shaft shortened, should cost a little over $100 to get done. This reduces your final drive ratio from 1:1 to .7:1.

[BarnieTrk]

Twan,
I would guess what 'bruceandersson' is referring to is a T170FT (Code-RTS) 4-speed OD transmission.
Here is some info on them: http://www.motivegear.com/tech_info/tra ... guide.html

I've ran a T170FT behind a stout 390-V8 for a while. Although the transmission had a large drop between 1st & 2nd gear, it was fine for cruising around WITHOUT a payload or towing. However, WITH a load, when starting out or backing up with a load, I would have to ride the clutch ALOT.

BarnieTrk

[Leeroy]

BarnieTrk Sorry I didn't see your question, unfortunately I had a little incident with the back wheel when some nice person attempted to steal it, the result was damage to the bed and an interesting experience I'll never forget as it all came flying offat 60mph.

I haven't had it back long enough to make a decent comparison, but I'll let you know.

[BarnieTrk]

WOW, Leeroy, I'm glad to hear you are OK; ...sorry to hear your Slick was injured though. Time for some locking lug nuts?

BarnieTrk

[ford6t5]

ok thanks, so it will fit the 300 that is good news.

hope to get it here for a decent price.

can i use the gearshifter on the steering wheel? ( or do i need a shifter on the floor)

so now i don't have to mess with the rear axle any more, this is way easier to get the rpm's down..

see ya

twan

[34rdztr]

twan, the one thing you will have to make sure of is the flywheel. from 83 and up the balance weight went to 50 oz,the earlier were 28 oz,if i am not mistaken your 300 is internally balanced and doesnt require a weight on the flywheel. if you want to use the flywheel that comes with the trans. you might can get by with removing the weight from it.
but yes it will bolt up ,just make sure the flywheel is correct on balance. hope this helps eddie

[ford6t5]

oke thats good to know.
what flywheel would fit the trans engine combo? pre '83? or is removing the weight enough? what is the deal if the weight isnt removed?


thanks

see ya

twan

[34rdztr]

it will shake your teeth out if you leave the weight on it. you should be able to buy an early or late flywheel for the 300 and it should fit just fine. just make sure the diameter is correct to fit your bellhsg. and when you put the trans in. make sure you ahve some endplay in the convertor. about 1/8-3/16. a few flywheels have different offsets but most years should fit your combination.
just make sure you purchase one for 300 ci

eddie

[cooter]

i used the 1986 f 150 flexplate from the 302, knocked the weight off and it workes well. Tv cable adjustment better be right on or sudden death will follow and it wont shift