NP435 Lubricant

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Aug 20, 1999 | 08:30 AM

jowilker

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From: Creedmoor, North Carolina

NP435 Lubricant

Aug 27, 1999 | 08:51 AM

Titus Smith

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NP435 Lubricant

I have a 66 with a New Process 435 4 speed transmission.
The original owner's manual says to
use SAE50 engine oil in the transmission. I have
gone to several shops including the Ford dealer
and cannot locate this lubricant. Does anyone
have a recommendation? Can I just use 80 or 90
wieght gear oil?

Aug 27, 1999 | 09:28 AM

jowilker

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From: Creedmoor, North Carolina

NP435 Lubricant

Titus, onother thing you might look at is non detergent. You might mix some 30w non det. with some 80w gear oil. The straight 80/90 could be a little too thick in the winter, and may need to be blended. You may want to look around for a synthetic gear oil.

John

Aug 27, 1999 | 09:31 AM

390fe

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From: Iowa

NP435 Lubricant

Any good parts store can order a case of 50 weight motor oil for you without any problem. Should cost about $1.25/quart. I would not put anything heavier than 50 wt in your tranny. It will not oil as well as 50wt and may cause hard shifting.

Aug 27, 1999 | 09:34 AM

390fe

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From: Iowa

NP435 Lubricant

By the way, any Harley Davidson shop will have an endless supply of 50wt oil!!

Aug 27, 1999 | 05:16 PM

Charles

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NP435 Lubricant

My project '65 F-350 has a well-used NP435, with plenty of bearing noise and whine in 4th gear, not bad in the lower gears. I had it drained and refilled by the local auto repair place, almost certainly with 80/90 gear oil (didn't know it called for 50).
Since the bearings are old, would I be better off leaving the 80/90 in (shifting is not difficult) or changing back to the specified 50-wt?

Aug 27, 1999 | 08:16 PM

390fe

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From: Iowa

NP435 Lubricant

In the summer you could probably get away with it. Most manual trannys use splash lubrication-the lower gears splash oil to the top gears. In the winter, 80-90wt doesn't splash very well. At least not here in Iowa.