using double overdrives with a cummins

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Jan 29, 2013 | 02:25 PM

F350moneypit

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Tuned

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using double overdrives with a cummins

I have been reading a lot of threads about cummins conversion and the subsequent gear changes people are doing to get the rpms down.

Has any one tried this combo:
cummins ->o/d tranny ->transfer case->gear vendors over drive unit?

as long as your not in four wheel drive with the O/D activated it seems like that could drop the rpms quite a bit.

Jan 29, 2013 | 03:59 PM

co425

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Look at the specs of a gear vendor. I don't think it will live long with even stock cummins torque. A mild cummins can easily pump out 600 foot lbs. I think your are better off with a rear end ratio change with the nv4500 5 speed or nv5600 6 speed. Both tranny's are the same overdrive ratio.

Jan 29, 2013 | 05:29 PM

lurch460

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I dunno bout that,I have seen some gearvenders go through hell on the dragstrip. I know there used to be two versions,one for higher hp and torque. I was at the SEMA show about 7 years ago and talked with gear vendors and I do recall them saying they had one available for diesels that made some serious power, but things might have changed since then. This is my plan if I ever get around to putting a cummins in.

Jan 29, 2013 | 06:04 PM

1972RedNeck

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From: Townsend, MT

If I had the money I would love to have 4.10's, a Getrag and a GearVendors in my Dodge. That would put the overall ratio at 2.33:1. Rigth now I have the 'rag and 3.07's, which puts me at 2.38:1.

Jan 29, 2013 | 07:41 PM

F350moneypit

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Tuned

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If I remember right most gear vendors units can handle 1500 hp but I don't know what torque values they're rated at.

Jan 29, 2013 | 08:05 PM

co425

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I could be wrong but I seem to remember it only being around 400 ish ft lbs. The hp numbers were there just not the torque. Unless they now make a diesel unit.

Jan 29, 2013 | 09:18 PM

Higbean

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It seems to me every time I talk to a guy with a Gearvendor, they are bitching about blowing em up. They seem like a good idea, but for the price of one, you'd be close to putting in an Alison or a built 47RH. Heck, you could find a 6 speed 48RE with the two OD's for dang near the same price I bet.