3 spd trans differ from 4 spd fyi...

[68swb]

Ok found this out the hard way, but for what i found out is that when i went to change my 3 spd trans to a np435 this past weekend on my truck with a 429 in it is that i had to change my pilot bearing, the pilot bearing that was in my 429 was flush with the rear of the crankshaft and i had to put a smaller dia. pilot bearing in the crankshaft that was recessed in to the crankshaft about a half inch or so. that being said, the differ. from the two trans is that the splines on the np435 start sooner than that on the 3 spd by about 1/4 inch or so. The hard way i found this out is i put the trans in my truck and got it stabbed and bolted it up to the bellhousing, but it would not bolt flush to the bell. so long story short i had to pull the motor out to get the bell housing off and inspect. i didnt have my camera with me but i do have the pilot bearing that i removed and i will take a pic of it along with some of my truck and post them. the pilot bearing has a nice imprint of the input shaft splines, hope this might help, and not to long winded and makes since....

[mmerlinn]

Sounds like your 435 input was longer than your 3spd input. If so, then your 3 speed bell was too short for your 435. Not sure whether that will cause any problems down the road or not.

[fordman]

the truck bells are suppose to be 6 1/2 inches deep the car bells are suppose to be 6 inches deep. if you are using the car top loaders then you want to use the car bellhousing because the car top loaders have a shorter input shaft. i think that is what i read.

[68swb]

the input shafts on each trans that i have are the same length i beleive because that is what i was thinking, that they where different lengths. i will recheck the measurments so i will know, but the tip of the input shafts where they ride in the pilot bearing where different lengths.... i am just going to have to re measure.....

[Hawkrod]

the truck bells are suppose to be 6 1/2 inches deep the car bells are suppose to be 6 inches deep. if you are using the car top loaders then you want to use the car bellhousing because the car top loaders have a shorter input shaft. i think that is what i read.

That only applies to car bellhousings, all truck bells are designed to use the same trans. The only time it is an issue is if you have a car FE or 385 series stick trans you need the shorter bellhousing. Hawkrod

[willowbilly3]

It seems like some prior discussion on putting the 429/460 in with the 351M/400 bell housing could require using 2-3 center plates? I never did it but I know one guy who did and he used 2 center plates, probably didn't know he could use a different pilot.

[Hawkrod]

It seems like some prior discussion on putting the 429/460 in with the 351M/400 bell housing could require using 2-3 center plates? I never did it but I know one guy who did and he used 2 center plates, probably didn't know he could use a different pilot.

The 351M/400 bell is shorter than a 429/460 bell so you do need a spacer to make that work but if you use a 429/460 bell on a 429/460 the same trans will work just fine (but off course 429/460 bells are like hens teeth). Hawkrod

[68swb]

the extra spacer plate i was thinking about because i remember there being some talk about that, i am using a 351m/400 bell on my 429, and i am using the same trans that was in the doner truck that had the 400 in it. But i was using the original 3 spd trans that was in my truck before with the same bell 400 bell and there where no issues, the truck orig. had a 300 in it thou, on sunday i will be back to working on my truck and i will take some pic if dont forget my camera and measure the inputshafts from each trans i have (3 spd and np435).... being that the different pilot bearing that i am now using i think that there is not going to be any problems with the fitting of the combo.....

[fordman]

sounds like you did the right thing.