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Discussion Starter · #1 ·
Hey, ive been lurking on this forum for a while now, and have learned a lot without asking questions, but now i have a question.

i do not plan to tow, and am thinking of using the sm465 or sm420 mostly because theyre cheap, tough, and fairly compact. price being the most important factor for me.

so, how does a 4bt drive with a "four" speed behind it? i know this trans is kinda like a 3 speed because of the low first gear. i read somewhere on here that the shift gaps were too large, but didnt the bread vans come with a 465?

input is necesary, but i really dont want to dump a lot of cash into a transmission.

THANKS!!
 

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They suck. 3 gears is not enough. If you want cheap buy yourself a ford M5R2 5 speed. They're close ratio, reasonably strong and very available. In fact I bought one today for $100 that appears to be rebuilt and it came with a 1356 t-case. I've installed 2 4BT's in front of M5R2's without any issue. The gear spread is perfect too.

If you're stuck on chevy you might try an NV3500. I say they're a pile of crap, but that's mostly because I hate working on them and they only run on special GM synchromesh fluid and they shift like crap for a light duty, late model 5 speed. All chevy 5 speeds are hard to find and expensive. The vast majority of late model chev trucks are automatics.
 

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If you are looking to do an "economy swap" using a transmission that is currently found behind the 4BT in P30 vans I would recommend the fully synchronized Borg Warner T-19 commonly referred to on here as the Ford setup. Ratios are 1st- 4.02; 2nd- 2.41; 3rd- 1.41; and 4th- 1.0 : 1. The SM-465 is a strong transmission but it is more like a three speed with a granny first gear that isn't synchronized. The SM-465 has a larger input spline than the T-19 but the trade off is it's basement ratio first gear. Then there is the availability problem and higher price of the 4BT to SM-465 parts which make using it a money pit if your van's engine didn't already come with it. The T-19 would be my first choice for a non overdrive transmission. My second choice would be the ZF series for the overdrive and price. My third choice would be the NV-4500 HD version found behind the Dodge Cummins.
 

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By all means, PLEASE put an NV4500 in your truck! I make a lot of money fixing New Ventures turd. They're a tough transmission, very high quality parts inside and very easy to work on, but they DO NOT hold up behind any diesel. Put them behind gas engines till the cows come home, but for your wallets sake do not put one behind a diesel if you have the option of something else (like a ZF). Go to quad4x4.com and read Dan's writeup on 5th gear failure. He does a very good job of explaining why the NV4500, even as beefy as it is, does not mate well with a diesel. Chevy 6.2's tear them up, no joke. It's just a bad design that you can't overcome unless you throw a bunch of money at one for a torque king shaft.

The ZF's are good units. Don't buy a broken one though. They are very complex and not you old toploader 4 speed inside, you won't be fixing one in your backyard!
 

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Discussion Starter · #7 ·
OH; i forgot to mention that the transmission and T-case have to be married, so no divorced t-case.

thanks for the quick replies.
 

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one other trans that was pointed out to me recently was an np 540 or 541. these can be found in old trucks. they have a super low 1st, the 4 usable gears and a direct top. i have one in my yard in an old dodge prime mover. from what i can see,they will go in where an np435 came from.
 

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I'm NOT picking a fight here, but: I chose the NV4500 because of its reputation for reliability. The lube issue is solved using Amsoil's version of the Meritor fluid, at 1/2 the price or less. That's what I run, no problems yet and never heard of any complaints from others.

Also I spent a whole bunch of time on the Dodge Diesel forums. Other than a few rare posts related to the 5th gear nut failure, a known problem on NV4500's, I never heard one single complaint, only praise. Many were swapping out the junk Getrags for NV4500s. I would have to say that in general the NV4500 still has a very good reputation among the Dodge Diesel crowd. They have been performing well even behind pumed up 6BT's. However I would not run one that didn't have the 5th gear nut repair.
 

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Every NV4500 HD from behind a 5.9 has a loose 5th gear/nut over 50K miles or so regardless of what nut design you use. Yeah, they still run, but without getting into massive detail on how NV4500's work and what problems the loose 5th gear causes when it is time for a rebuild. I'd say there are far better and considerably cheaper options out there.
 

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The sm465 will work just fine but as you know there isn't a overdrive and if you can live with it than do so .

The Nv4500 is a very good trans and they will live behind a 5.9 Cummins ,yes they do have problems Dodge mostly .The Gm have less of problems.

Any body can tear up any trans if they want to !

CrewCab59
 

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. I'd say there are far better and considerably cheaper options out there.
Name them. :happyfinger:

Find me a durable, dieselproof transmission with overdrive, for less than the $1500 a NV4500 costs.

4L80e? Nope.
E4AOD? Nope.
Allison? Nope.
NV5600? No.
RoadRanger? Nope.
GearVendors add-on? Not even close to cheap.

The 3053a??????? MAYBE. But not in a 4wd truck. And they're so much fun to shift, too. :D

I'm all ears if you've got some options, I would love OD on the cheap. :D
 

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What are you using vehicle for, mostly on or off road? I used NP435 because I wanted stump puller gear, but before that, I had an OD 4 speed out of a 79 Bronco and it ran fine just tall between gears but if a light vehicle it works well. Cast iron, top shifter and bolts right in place of T-18/19.
 

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If its a light vehicle, I liked the OD 4 sp. But first gear is tall like a Ford 303(3 to 1) or taller I think.
 

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1500 for an nv4500 !:eek: i rang up today and 3500 $aus. yeah, and 4 grand for a gear vendor o/d. what about the ranger o/d ? they are 1500 odd $us. they slip between the box and bellhousing. moves the shifter back 7 inches.
 

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I can barely make a perfect NV4500HD for $1500 buying cores at $300 a pop. Don't think for a minute you can buy a perfect cummins NV4500 for that price; you'll be very suprised to find out the NV4500 you just bought is filled with chinese and asian goodies that might make it past the warranty period.

ZF's are cheap and hold up. They break, but not nearly as often as NV4500's do. And yes, ZF S5-42's do hold up just fine behind even tweaked 24 valves.

You can buy an S6-650 for around the same as an NV4500. An S6-650 makes an NV4500 look like a playtoy.
 

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I paid $800 for my '96 Dodge NV4500, with fresh synchros and seals, including shipping from TX to CA.
 
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