NP435 into 7.3 Diesel Super Duty

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Oct 11, 2005 | 10:56 AM

bigblue

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Joined: Sep 1999

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From: Minneapolis

NP435 into 7.3 Diesel Super Duty

Will the NP435 from my 86 F150 inline 6 be a direct swap into my 95 Super Duty with 7.3 Diesel?
If not, what is needed?
Thanks

Oct 11, 2005 | 02:04 PM

andym

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Joined: Mar 2002

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From: Bonita Springs FL

You'll need a new bellhousing from an NP435 that was behind a diesel or a 460. You'll also need the crossmember for the NP435.

Good luck, sounds like a fun swap.

Oct 11, 2005 | 06:59 PM

cleatus12r

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Joined: Apr 2004

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From: Reed Point, MT

One thing you're also going to want to consider is the rear axle gearing. With a 1:1 ratio in 4th gear, your 7.3L will be spinning some hella-high RPM going down the highway.

Cody

Oct 12, 2005 | 09:57 PM

Franken-Truck

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Joined: Apr 2003

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From: Virginia Beach

The 460 and Diesel have different bell housing bolt patterns. The gas NP435 has a wide ratio gear set, while the diesel version (if there is one) has the close ratio gear set. With a gas tranny behind your diesel, you'll rev way out of your power band and be shifting way too soon (unless you have like a 3.00 rear end). . . just an example, the 1st gear in your NP435 is 6.69:1, while a diesel is around 4:1. Cody brings up a good point about no overdrive. Also, if your swapping out a ZF for whatever reason, you'll need to more than likely modify your drive shafts, come up with a custom crossmember, and you might have difficulty adopting a slave cylinder setup to activate your clutch (external slave). If your swapping out an auto. . .then you'll have all kinds of problems to deal with.

I'd keep an eye for a proper replacement