what does your tach read at 60mph

[nolan in blaine]

I was just looking into swapping rear gears or even to an overdrive trans. Wanted to see what some of you guys where turning for R's at 60.

I have a 70 F100 with a 302, C4, and 3:50 gears. and 225-75-15 tires in the rear. At 60mph im at about 2,850 rpms...

What about you?

[j41385]

I just swapped my c6 out for an aod trans. My rpms were 2850 at 65 if I recall correctly. Now its 1600 or so at the same speed in 4th gear od.

[nolan in blaine]

what do you have for rear gears? tire size?

[j41385]

If my gears are original and Im almost sure they are, they are 3.00:1. The rear tires are Bf Goodrich P275/60R15.

[BobbyFord]

If my gears are original and Im almost sure they are, they are 3.00:1. The rear tires are Bf Goodrich P275/60R15.

3.00:1 was not an option for your truck.

[j41385]

My truck is a 72, and I put a 68 grill on it, so I call it a 68 it is the 02 axle code.

[basketcase0302]

I've only had BC #16 up to 60 for three short periods since getting her back on the road.
At 60 I'm spinning the "little 302" around 3100 RPM with the C-6 and D-70!
Sure hope to be able to save up enough to get an overdrive someday soon!

[nolan in blaine]

whats your rear gears?

[basketcase0302]

nolan in blaine on Sat Oct 23, 2010 3:58 pm
whats your rear gears?

Nolan, sorry about that (forgot to post ratio)...

My trucks axle has the original open carrier with 4.10 gears in it. I don't really want to go to a higher ratio (for better fuel mileage) now as I really like my low end torque where it's at present.

[nolan in blaine]

mine dont really haul anything too heavy. Id like to go with a taller gear then a 3.50 for mileage cause i do a lot of freeway driving. I wonder if i could pull 2.73's . Even with a two barrel on the 302 it still sucks on the interstate. If i find a taller geared 9 inch can i pull out the whole 3rd member and swap it with no problems. (like a direct bolt it). Would rather do an AOD but not sure if i wanna tackle the swap right now.

[j41385]

The C6 to AOD swap was pretty much bolt in, and it should be simpler for a c4. The only thing I had to do that was custom was shorten the front part of the 2 piece drive shaft. If there isnt a place in Blaine, Hop over the border and I bet there will be. I been through there alot starting at 19, and ending when I turned 21. It's 19 to drink in BC.

[nolan in blaine]

well if its that easy i think ill start looking for a aod....

[j41385]

If you do get an aod my suggestion is to get one from a 1992 or 1993 F150, those are the "holy grail" of aod transmissions in that they are the strongest ones ford made. They have the most clutch packs, a 2 inch od band (all other aod's have the 1.5 inch band), wide ratio gearset, and the rare and desirable A servo.
The A servo clamps the od band down harder than the B or C servos. The C servos came in v6 cars, the B servo came in mustang gt's and things like that, and the A servo came in the thunderbird super coupe and the 92 and 93 F150. You can upgrade any AOD with the parts I mentioned, but getting one with the parts already in it is nice.