Medium Duty (13" Clutch) np435 questions

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powerwagon54
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Re: Medium Duty (13" Clutch) np435 questions

Post by powerwagon54 »

Yes the 67-68 383 bell housing assemblies are hard to find. I have 2 right now.

712edf
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Re: Medium Duty (13" Clutch) np435 questions

Post by 712edf »

powerwagon54 wrote:Yes the 67-68 383 bell housing assemblies are hard to find. I have 2 right now.
Just curious, were the 383 flywheels the same as A/LA flywheels of that era? In other words would a 318 poly or LA flywheel fit the 383?

I know the 143 tooth flywheels of the 69-88 mech clutch area were interchangeable from LA & B/RB, if the balance was correct.

Bucky
1966 W500
1975 W600
1978 W200 club cab

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Re: Medium Duty (13" Clutch) np435 questions

Post by powerwagon54 »

The LA flywheel will bolt to the 383. But they are only an 11 inch clutch flywheel and are 172 teeth, The 383 flywheel is a 12 inch clutch flywheel and are 186 teeth. So the starter will not engage an 11 inch flywheel. You can ask Terry about the starter differences between a 318 and a 383.

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Re: Medium Duty (13" Clutch) np435 questions

Post by 712edf »

^^Thank you for that clarification. I suspected there was a difference, because 383 flywheels, bellhousings & starters seem to be sought after & harder to come by.

Bucky
1966 W500
1975 W600
1978 W200 club cab

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Re: Medium Duty (13" Clutch) np435 questions

Post by Zpsull01 »

powerwagon54 wrote:You are not grasping the fact that the big blocks in those medium duty trucks were 361 and 413. They have 8 bolt cranks and that flywheel is not going to work on a 440.
I knew there were 6 and 8 bolt setups but I thought the 8 bolt was the less common. Apparently that's not the case. I assume there's not a conversion flywheel and something is different on the 8 bolt bellhousing that will not allow me to purchase a flywheel for a 6 bolt setup and use it in the 8 bolt bell.
712edf wrote:The only thing about mine is it has a NP540 instead of the NP435.

Bucky
What are the differences in the 435 and the 540 besides being a 5 speed? Same bolt pattern, input shaft, etc?

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Re: Medium Duty (13" Clutch) np435 questions

Post by 712edf »

The 540 only came in medium duty's, only had the larger input shaft. Bolt pattern is different than the 435 but I think some bells are drilled/tapped for both. Input shaft length is possibly different. It is physically a larger, longer & heavier transmission.

540 was offered in OD configuration, but NOT in a Dodge that I'm aware of.

Bucky
1966 W500
1975 W600
1978 W200 club cab

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Re: Medium Duty (13" Clutch) np435 questions

Post by 712edf »

The crank flange of an 8-bolt crank sticks out from the block a different distance than does the flange of a 6-bolt crank. To keep the flywheel from being too deep into the bell there is a slight "offset" built into the design of the flywheel, meaning the center section isn't directly inline the plane of the machined surface of the flywheel. (My terminology is not the best. Just visualize the different offsets/backspacing of car wheels, or water pump pulleys, to get a picture of what I'm trying to describe).

In other words one flywheel is flatter than the other type.

Bucky
1966 W500
1975 W600
1978 W200 club cab

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