1974 F100 Custom Gear ratio?
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sargentrs
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Re: 1974 F100 Custom Gear ratio?
I had a 3.25 ratio in my '70 with the Ford 3 spd manual. It wasn't too bad but still wound up pretty high at 80 mph. When they crapped out I swapped in a set of 3.89 gears. I picked up a lot out of the gate but she was screaming at 75 mph. For my build I'm going back in with some 3.00 gears to pick up more top end at lower rpms. I'm not really concerned with squalling tires and drag racing the quarter mile. I'm after mileage and lower rpms with a higher top end for highway driving.
Randy
1970 F100 Sport Custom Limited LWB, 302cid, 3 on the tree. NO A/C, NO P/S, NO P/B. Currently in 1000 pcs while rebuilding. Project thread: http://www.fordification.com/forum/view ... 22&t=59995 Plan: 351w, C4, LSD, pwr front disc, p/s, a/c, bucket seats, new interior and paint.
1987 F-150 XLT Lariat, 5.0/C6 auto.
1970 F100 Sport Custom Limited LWB, 302cid, 3 on the tree. NO A/C, NO P/S, NO P/B. Currently in 1000 pcs while rebuilding. Project thread: http://www.fordification.com/forum/view ... 22&t=59995 Plan: 351w, C4, LSD, pwr front disc, p/s, a/c, bucket seats, new interior and paint.
1987 F-150 XLT Lariat, 5.0/C6 auto.
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Delta41
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Re: 1974 F100 Custom Gear ratio?
Any ideas as to how or where i can find out the original ratio?
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sargentrs
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Re: 1974 F100 Custom Gear ratio?
Is your 3rd member/pumpkin/chunk the truck's original? If so, there should be a metal tag hanging on one of the bolts. About 2/3 down on the this page will show you what it looks like and how to decipher it...http://www.kevinstang.com/Ninecase.htm If it's not, or if the tags missing that's a different story. Your door sill plate will identify the rear axle but due to the variety of options and configurations available the gear ratio was not detailed on it, at least I don't think so. To identify your current gear ratio, without the tag, you'll have to count the teeth on the ring gear and on the pinion gear and divide. i.e. my ring rear has 39 teeth and my pinion gear has 13. 39/13 = 3.00 gear ratio.
Randy
1970 F100 Sport Custom Limited LWB, 302cid, 3 on the tree. NO A/C, NO P/S, NO P/B. Currently in 1000 pcs while rebuilding. Project thread: http://www.fordification.com/forum/view ... 22&t=59995 Plan: 351w, C4, LSD, pwr front disc, p/s, a/c, bucket seats, new interior and paint.
1987 F-150 XLT Lariat, 5.0/C6 auto.
1970 F100 Sport Custom Limited LWB, 302cid, 3 on the tree. NO A/C, NO P/S, NO P/B. Currently in 1000 pcs while rebuilding. Project thread: http://www.fordification.com/forum/view ... 22&t=59995 Plan: 351w, C4, LSD, pwr front disc, p/s, a/c, bucket seats, new interior and paint.
1987 F-150 XLT Lariat, 5.0/C6 auto.
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Donnie
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Re: 1974 F100 Custom Gear ratio?
If your tag is missing, post back & we will help you find the ratio without counting the teeth
Donnie
Donnie
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Delta41
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Re: 1974 F100 Custom Gear ratio?
unfortunately it's in storage and i can't get to it until mid december... I'm away on an exercise and then to norway... I was hoping to get as much info while i'm away...
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sargentrs
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Re: 1974 F100 Custom Gear ratio?
We'll be here when you get back!
Randy
1970 F100 Sport Custom Limited LWB, 302cid, 3 on the tree. NO A/C, NO P/S, NO P/B. Currently in 1000 pcs while rebuilding. Project thread: http://www.fordification.com/forum/view ... 22&t=59995 Plan: 351w, C4, LSD, pwr front disc, p/s, a/c, bucket seats, new interior and paint.
1987 F-150 XLT Lariat, 5.0/C6 auto.
1970 F100 Sport Custom Limited LWB, 302cid, 3 on the tree. NO A/C, NO P/S, NO P/B. Currently in 1000 pcs while rebuilding. Project thread: http://www.fordification.com/forum/view ... 22&t=59995 Plan: 351w, C4, LSD, pwr front disc, p/s, a/c, bucket seats, new interior and paint.
1987 F-150 XLT Lariat, 5.0/C6 auto.
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Delta41
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Re: 1974 F100 Custom Gear ratio?
well i'm back and she's out! first drive was yesterday and she runs like a top! I can't find the axle ID plate but i was able to get an axle code off the driver door id plate...
trans -> F
Axle -> 17
DSO -> A1
I followed the instructions on the earlier posted link and i THINK it's a Ford 9"...
Now i'm having a hell of a time finding info from this number. Do you guys have a link to get this info or could you provide any? Tranny type would be appreciated too (not sure if its a t-18 or T-19)
Thanks a bunch guys
trans -> F
Axle -> 17
DSO -> A1
I followed the instructions on the earlier posted link and i THINK it's a Ford 9"...
Now i'm having a hell of a time finding info from this number. Do you guys have a link to get this info or could you provide any? Tranny type would be appreciated too (not sure if its a t-18 or T-19)
Thanks a bunch guys
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sargentrs
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Re: 1974 F100 Custom Gear ratio?
trans -> F (T18)
Axle -> 17 (Ford 9" - 3.25 gear ratio)
DSO -> A1 (Ford of Canada - Central (Lincoln/Mercury))
Here's the link to our sister dent side site, Fordification.net http://fordification.net/tech/vin.htm for a full deciphering of your VIN and Data plate.
Axle -> 17 (Ford 9" - 3.25 gear ratio)
DSO -> A1 (Ford of Canada - Central (Lincoln/Mercury))
Here's the link to our sister dent side site, Fordification.net http://fordification.net/tech/vin.htm for a full deciphering of your VIN and Data plate.
Randy
1970 F100 Sport Custom Limited LWB, 302cid, 3 on the tree. NO A/C, NO P/S, NO P/B. Currently in 1000 pcs while rebuilding. Project thread: http://www.fordification.com/forum/view ... 22&t=59995 Plan: 351w, C4, LSD, pwr front disc, p/s, a/c, bucket seats, new interior and paint.
1987 F-150 XLT Lariat, 5.0/C6 auto.
1970 F100 Sport Custom Limited LWB, 302cid, 3 on the tree. NO A/C, NO P/S, NO P/B. Currently in 1000 pcs while rebuilding. Project thread: http://www.fordification.com/forum/view ... 22&t=59995 Plan: 351w, C4, LSD, pwr front disc, p/s, a/c, bucket seats, new interior and paint.
1987 F-150 XLT Lariat, 5.0/C6 auto.
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Delta41
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Re: 1974 F100 Custom Gear ratio?
Thanks Sarge, you just helped me save a couple hundred dollars on new gears.
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sargentrs
- 100% FORDified!
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Re: 1974 F100 Custom Gear ratio?
No prob! Had 3.25's in mine to start but swapped 'em out for some 3.89's. Wish I still had the 3.25's. Enjoy!
Randy
1970 F100 Sport Custom Limited LWB, 302cid, 3 on the tree. NO A/C, NO P/S, NO P/B. Currently in 1000 pcs while rebuilding. Project thread: http://www.fordification.com/forum/view ... 22&t=59995 Plan: 351w, C4, LSD, pwr front disc, p/s, a/c, bucket seats, new interior and paint.
1987 F-150 XLT Lariat, 5.0/C6 auto.
1970 F100 Sport Custom Limited LWB, 302cid, 3 on the tree. NO A/C, NO P/S, NO P/B. Currently in 1000 pcs while rebuilding. Project thread: http://www.fordification.com/forum/view ... 22&t=59995 Plan: 351w, C4, LSD, pwr front disc, p/s, a/c, bucket seats, new interior and paint.
1987 F-150 XLT Lariat, 5.0/C6 auto.
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Donnie
- Blue Oval Fanatic
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Re: 1974 F100 Custom Gear ratio?
Delta, since your data plate is missing on your diff. case.........that would red flag me as to someone being in there + it over 35 years old.
You really need to verify what gear set you have....this can be done ,as I said before, without counting teeth...It is done by counting wheel revs + watching the driveshaft...need more instructions, write back........Donnie
You really need to verify what gear set you have....this can be done ,as I said before, without counting teeth...It is done by counting wheel revs + watching the driveshaft...need more instructions, write back........Donnie