Slick 60's

Right now it's a Dana 60 with 4.10 gears and an NP435 (soon to be a C6)

235/85-16 tires (31.7") diameter

At 69mph, the engine is running at 3000 rpms.

I'm thinking of regearing to 3.3x which will put the engine rpms just under 2500 rpms at 69mph.

Thoughts pro or con on doing this?

ah-hem

Anyone out there running 3.3x gears?

Mike, After my son replaced the 300 I6 3sp man. in my/his old 66 with a 302/C6 auto he came back after his first Hiway test run and said it sounded like it was winding up to tight. He replaced the stock 3:70 chunk with a 3:25 made all the difference in the world. Of course changing out the gears in the dana takes a bit more time than a 9" Ford. Have you considered changing out the dana for a 9" Ford?

edited 602 to 302 , bad eyes & fat fingers

Same thing here, I am looking for a NV4500 and backing it up with a GV. It should turn 1792 rpms @ 70mph with a 4.30 gear swap. Good excuse to buy a torquer 58-60 430 Lincoln engine.

Obsa wrote:Mike, After my son replaced the 300 I6 3sp man. in my/his old 66 with a 302/C6 auto he came back after his first Hiway test run and said it sounded like it was winding up to tight. He replaced the stock 3:70 chunk with a 3:25 made all the difference in the world. Of course changing out the gears in the dana takes a bit more time than a 9" Ford. Have you considered changing out the dana for a 9" Ford?

edited 602 to 302 , bad eyes & fat fingers

I thought about a Ford 9" but then I'd be going to 5 lug wheels, which isn't a bad thing. Just means all new wheels and tires, plus I'd have to do the front as well (I have power discs).

I'm also a Jeep off-roader and there are a lot of 4WD shops around here that regear Dana 60's daily. There is one guy that will do the labor for $175 if the axle is out or $250 if it's in. I'll need to buy the master rebuild kit with the ring a pinion. I've rebuilt Dana 44's when I used to be a heavy equipment mechanic. I could do it but don't really have all of the tools now. Plus, all the putting it together, dial caliper, take apart, repeat, repeat, repeat would drive me crazy now.

When I still had the 292 3spd., I swapped the 3.89's with a 3.25 Trac-Loc and it made a big difference in the way it cruised. The engine seemed to be wound out a 45mph with the 3.89 gears.

I think you'll like the change if you drive on the highway much.

Doing some research (http://en.wikipedia.org/wiki/Dana_60) it looks like the highest gear ratio for a Dana 60 is 3.31. I think that would work great.

I hit up one of the vendors on my Jeep forum to see what he comes up with.

The bearings were shot in my 3.89lsd so when I had them changed I had the gearset swapped to 3.5 (9")
I run 275/55 17's which is 29" and it's great. The wind/road noise is louder than the engine now. I did consider 3.25 but I was a bit worried that It may labour the transmission too much if I towed anything. (fmx) I could have gone lower but I am more than happy with the 3.5 and 29" tyres. Think it sits on 2500 at 100km/h
Fuel economy didn't change much however, it did improve, but only marginally.

I bought a 1966 f250 custom cab camper special for parts and it has a Dana 60 that im not going to use and need to sell it anyway. I don't know if it has a id tag to try and figure out the gearing (if it would be different than yours) but I can check if your interested. But it will need a good cleaning.

I don't know if this really helps, but I pluged your numbers into my spreadsheet I did.

Let me know if you want me to change the inputs at all.

RedneckCowboy wrote:I bought a 1966 f250 custom cab camper special for parts and it has a Dana 60 that im not going to use and need to sell it anyway. I don't know if it has a id tag to try and figure out the gearing (if it would be different than yours) but I can check if your interested. But it will need a good cleaning.

Yes, let me know what gears are in it. If it's a CS truck though, might have 4.56.

MadMaxetc wrote:I don't know if this really helps, but I pluged your numbers into my spreadsheet I did.

Let me know if you want me to change the inputs at all.

Thanks, that's awesome!

I just created this gear ratio calculator. Don't edit any values in RED

https://docs.google.com/spreadsheet/ccc ... WRqenRCcGc

Big Mike,

It seems you are wanting to lower your operating rpms @ highway speed. Is your reason for wanting to reduce the engine rpms have to do with the amount of fuel consumption or more specifically, your fuel cost?

If so, how much less fuel do you think your '65 F250 352-V8 will burn by reducing the current engine operating rpms of 3,041 rpms (4.10 gears) down to 2,455 rpms (3.31 gears)?

Once you have that answer, then you can compare the fuel cost savings to the total cost of the proposed gear change.

BarnieTrk

BigMike wrote:

RedneckCowboy wrote:I bought a 1966 f250 custom cab camper special for parts and it has a Dana 60 that im not going to use and need to sell it anyway. I don't know if it has a id tag to try and figure out the gearing (if it would be different than yours) but I can check if your interested. But it will need a good cleaning.

Yes, let me know what gears are in it. If it's a CS truck though, might have 4.56.

I checked the axle its got 4.10 gears. Sorry I can't help with the axle, if you do need any other parts on the frame/suspension just let me know.

What about going with an overdrive tranny? This should reduce your final ratio by 30% without sacrificing the low end.

bruceandersson wrote:What about going with an overdrive tranny? This should reduce your final ratio by 30% without sacrificing the low end.

I'm planning on a C6 later this year. Is there an AOD for the FE?

My Jeep vendor, River City Offroad, can only find 3.54 as the highest gears for the Dana 60. He's going to continue to look.

Did Ford 9" rears come with 8 lugs?

BigMike wrote:

bruceandersson wrote:What about going with an overdrive tranny? This should reduce your final ratio by 30% without sacrificing the low end.

I'm planning on a C6 later this year. Is there an AOD for the FE?

My Jeep vendor, River City Offroad, can only find 3.54 as the highest gears for the Dana 60. He's going to continue to look.

Did Ford 9" rears come with 8 lugs?

9" did not come with 8 lugs

3.54 is the highest D60 ratio,

not that it helps you but there is a 1/2 ton version of the D60 posi, 3.54 that was used in some ford/dodge applications back in the 60s uses the 5x 5 1/2 wheels




i keep reading stuff like "my engine is topping out @ 45 mph with 4.10" etc.

and these statements cannot possibly be true as i regularly drive my y block powered 4x4 with 4.56 at 70 mph and its no problem, theres more left.

also i once did a test in a 65 f350 with fe and 4.88 gears and passed the 100 mph mark. yes it took a while to get that speed up and yes it was a bit noisy inside but there was only a bare floor, i did not top out, i slowed down because i did not need or want that 100 mph ticket plus the straight part of the road was ending.

if you are wanting to save the little bit of fuel and the gear noise, taller tires and an overdrive unit are the way to go if you ask me. i keep trying to talk a friend into parting with the gear vendors unit he has

4.10 rear with a .78 overdive = 3.19
4.56 = 3.55

i do not wish to mess with changing/losing my low gears nor do i care to play with matching trans to my engine be it a t-5 or whatever. that in my book makes the stand alone OD units my choice if i want to do something.

Thanks ICEMAN

I got the 3.31 from Wiki on the Dana 60.

I want to go to a higher gear ratio so that the engine isn't screaming on the highway. The OD units are really pricey. It would probably be cheaper to install an AOD with an adapter kit.

If I was going to go with 5 lugs, I'd use a 9" rear. I'd really like to have a nice set of Cragar S/S wheels on the truck but don't want to invest that much in it.

ear plugs will be cheapest.