NP435 when slowing on downshift

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Apr 20, 2016 | 10:46 PM

chukar

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From: Upland CA

NP435 when slowing on downshift

It's a '74 std cab with the NP435. Acceleration sounds normal, though what would I know, it's the first ford truck of this vintage I've ever owned. But when slowing and especially downshifting into third and then second, it really growls. This normal???

Apr 20, 2016 | 10:58 PM

HIO Silver

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From: NorCal

What do you mean by "growls"?

Apr 20, 2016 | 11:06 PM

mountain dewd

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From: O-O-O-Oreilly's

You're probably fine. Check the fluid and make sure there is no glitter in the gear oil. 435s are pretty noisy.

Apr 21, 2016 | 12:02 AM

chukar

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From: Upland CA

Quote:

Originally Posted by HIO Silver

What do you mean by "growls"?

Like there's .25" between the teeth and the space is filled with small pebbles. Just noisier than any trans I've ever heard before. Forward gears all normal sounding.
Drained and replaced gear oil when I first got it home. Nothing in the oil that drained out that looked suspicious.