np435 downshifting noise

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Feb 10, 2015 | 05:34 PM

Ford Guy87

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np435 downshifting noise

Hey guys I have a 78 F150 4x4 flareside has a 400 with a np435 with a np205. I recently put a new clutch in it. Has a squealing noise downshifting into 3rd. After changing it the noise was still there. So I bit the bullet an had the tranny completely overhauled. Well after driving it 3 days the noise is back. Sounds like a throw out bearing but everything is new. Not sure if the clutch needs to be adjusted. It's under warranty but wanted some input from other people on what it might be.

Feb 10, 2015 | 07:48 PM

77&79F250

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Do not mess with it at all, I am sure if you do, it will void any warranty that shop gave you. Rub your lucky rabbit's foot on the way to the shop.

Take it back and let them fix it, tell them it was NOT doing it when you picked it up from them....if you are lucky they will cover the repair.

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Feb 10, 2015 | 07:54 PM

Ford Guy87

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That's what I'm going to do. I should mention all the clutch linkage an related was replaced to. New adjusting rod. Z bar. Bushings. An clutch fork.

Feb 10, 2015 | 08:41 PM

Blue and White

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Is the bell housing original to the block? If not, runout may need dialed in. If the bell housing is not original or if the block was line bored, center of the transmission and crank may be different. A dial gauge mounted to the flywheel or crank flange set up to indicate run out with the round bell housing to transmission mount bore will tell. <.003" run out preferred, .005" max. Offset dowels can be used to adjust as needed.

If the run out is excessive, it may cause noise, wear and short transmission input bearing life.

Feb 10, 2015 | 08:48 PM

Ford Guy87

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Well it was originally a 351m then replaced with a 400. Been like that since 91 just in the last month it's started making the noise

Feb 13, 2015 | 06:00 AM

Ford Guy87

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Well I took it in an of course it didn't make a single noise. But still does occasionally. Seems the harder you use the tranny the less it does it. Left work tonight went to hit 4th gear an grinded then popped in. Guess just keep driving it.