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Will an NP-435 with a Dana 20 adapter fit a 351w?

la hi

Jr. Member
Joined
Feb 11, 2014
Messages
103
I am replacing my 170ci 6 with a 351w that I will have rebuilt. I have not heard much about the np-435 transmission and would like to know it this transmission will work?
Or would a toploader 4 speed work better?
I have a 66 U14 , 3 on the tree and some of you have said that the 3 speed will not hold up.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,960
Yes, it will work just fine.

The issue with the 3-speed is you are dealing with one for an I6 application, not a V8 application.

What works best, depends on how it will be used.
 

ScanmanSteven

Bronco Guru
Joined
Dec 19, 2010
Messages
1,129
A NP435 will definitely hold up, they were used in lots of F250s. The weak link will now be the Dana20, but again, depending on how you use it depends on if anything breaks.
 

SavageBurro

Sr. Member
Joined
Aug 12, 2013
Messages
588
not to talk you out of the np435, they're great transmissions. I run one and have run a handful over the years. excellent way to get a granny low but still no overdrive.. there are however other trans out there that might better meet your needs depending on what you're looking for. for example a zf5 has a decent granny low and a nice overdrive. takes a bit more to fit (tad more expensive trans and adapters) and likely require driveshaft mods. food for thought
 

Cortez

Bronco Guru
Joined
Jan 29, 2009
Messages
1,193
If you go with the np435, it’s going to require at least 1” body lift because it sits a little higher.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,960
If you go with the np435, it’s going to require at least 1” body lift because it sits a little higher.

I know a lot of people who have run them without a body lift. Including myself. So a body lift isn't exactly a requirement, although it does make things easier. Especially with the 351. Real easy to run out of hood room.
 
OP
OP
la hi

la hi

Jr. Member
Joined
Feb 11, 2014
Messages
103
Thanks all,
I will let you know the results when I do it. I am thinking that I will use the 3 speed till it breaks. Meanwhile I will keep researching.
larry
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,960
Don't use the 3-speed. It's too short. To use it you will have to butcher the firewall to shove the engine back too far. this also puts the oil pump directly above the front diff. The transmission is fairly strong, it's the physical size that is the problem. If you insist on using a 3-speed, find a used V8 version (and matching shift rods).
 

sykanr0ng

Bronco Guru
Joined
Aug 11, 2014
Messages
5,363
For a three speed from a V8 ask the guys on Colorado Classic Broncos, many of them have swapped theirs out for something else and may not have taken them in for scrap yet, they are hard to give away around here.
 

Nothing Special

Sr. Member
Joined
Nov 25, 2016
Messages
805
I've got a 3-speed from my V8, as well as the Dana 20 collecting dust in the garage. I can't say that I'm real eager to figure out how to ship it, but if anyone wants the pair of them (and/or an AOD with manual valve body and Dana 20 adapter) we can maybe figure something out.
 

Bronco Junkie

So Cal Broncos
Joined
Feb 29, 2012
Messages
3,233
I know a lot of people who have run them without a body lift. Including myself. So a body lift isn't exactly a requirement, although it does make things easier. Especially with the 351. Real easy to run out of hood room.

Right, not a requirement but most likely need to cut a big hole in the floor.
 
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