ZF trans & gears
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horseplay
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ZF trans & gears
Curious how many of you are running ZF 5speed. What gear ratio & tire sizes are you running.
- landshark
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Re: ZF trans & gears
35" tires and 4.56 gears
1976 Bronco "Green, Yellow, whatever", 1969 Bronco "Red", 1972 Bronco Stocker "Kind of Blue/Grayish"
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horseplay
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Re: ZF trans & gears
What RPM are you running at 55mph in 4th & 65-75 in 5th. Would you consider 4.88 ?
- sykanr0ng
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Re: ZF trans & gears
You also need to ask what engine they have.
A 5.0L / 302 has a different RPM range for best power than a 351 / 5.8L or a 400 and then there are the various strokers.
I don't have it done yet but 34" to 35" tires (metric, next maybe?) and 4.88 is my plan.
Engine?
Explorer 5.0L or 5.0L based stroker.
A 5.0L / 302 has a different RPM range for best power than a 351 / 5.8L or a 400 and then there are the various strokers.
I don't have it done yet but 34" to 35" tires (metric, next maybe?) and 4.88 is my plan.
Engine?
Explorer 5.0L or 5.0L based stroker.
"You say overkill like it's a bad thing."
- Digger
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Re: ZF trans & gears
horseplay wrote:What RPM are you running at 55mph in 4th & 65-75 in 5th. Would you consider 4.88 ?
Running 4.56s and 35's with 351W. Would not go to 4.88s with my setup. I could handle 4.10s and be fine.
Cummins R2.8 diesel, ZF5, AtlasII, HP44/BB9, ARBs, coiled / linked suspension, 37" KO2s, full cage, bumpers, etc.
Build Thread: http://www.coloradoclassicbroncos.com/viewtopic.php?f=3&t=5420
Average 23.5 mpg, Best tank: 26.3 mpg
Build Thread: http://www.coloradoclassicbroncos.com/viewtopic.php?f=3&t=5420
Average 23.5 mpg, Best tank: 26.3 mpg
- Jesus_man
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Re: ZF trans & gears
351 EFI, 35's and 4.10's. That setup could cruise all day long on the Interstate with ease. But my rig is more of a crawler, and I want to go to a 37", so I may regear at some point. Or perhaps build more beefy axles in the gear ratio I need, while still maintaining the ability to travel 70+mph.
1973 Bronco, 351 SEFI, Locked, discs, 35's ZF-5spd and Atlas 4spd. 235:1 Crawl Ratio. It may be ugly, but it's slow.
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http://www.ucora.org
- landshark
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Re: ZF trans & gears
I have a 400 (modified) runs about 2400 RPM at about 72MPH with 35" tires and 4.56 gears
I can run it in 5th at 35mph - 55mph no problem, well under 1500rpm at those speeds but as mentioned because of the size of my engine it has plenty of grunt at those rpms.
4.56 seems perfect for me and my needs.
If i went to 37's I would regear to 4.88. 33's I would move to 4.10's
I can run it in 5th at 35mph - 55mph no problem, well under 1500rpm at those speeds but as mentioned because of the size of my engine it has plenty of grunt at those rpms.
4.56 seems perfect for me and my needs.
If i went to 37's I would regear to 4.88. 33's I would move to 4.10's
1976 Bronco "Green, Yellow, whatever", 1969 Bronco "Red", 1972 Bronco Stocker "Kind of Blue/Grayish"
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horseplay
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Re: ZF trans & gears
Thanks for the input sounds like 4.56 for a combination use is the way to go.
- Justin
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Re: ZF trans & gears
That's what I'd do. I'll be running 4.56 with 37s, but am planning lower t-case gears.
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HIX
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Re: ZF trans & gears
I am running 32s and stock gearing...doesn't help you out much but there it is.