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Hey Bolters,

I tried searching for this already and I've yet to find a similar topic.

I've been slowly gathering parts to get the drive-train updated on my '53 pickup. I recently got a 1/2 ton rear end off of a '64 Chevy 1/2 ton, so I can change to an open drive shaft which I'm pretty excited about, but now I'm trying to begin research on different transmissions and which would be best for my purposes.

I am going to put a SBC 350 in the truck with about 350 hp and similar torque, I'm keeping the 3.73 gearing in the rear and I know I want a reliable manual transmission, but that's it. Concerning transmissions, I know Muncies and Tremecs are good, but they are expensive.

Any advice on where to start researching transmissions and what I should consider would be great. Also any advice on good manual transmissions that are affordable and common would be appreciated as well.


Sincerely,
SEMPERFInk

OK, we got the Manual transmission, and we got cheap, what we didn't get is how many gears... 3, 4, 5, 6? What are you looking for. Be well aware that any manual transmission you will find for that HP and torque rating won't be cheap.

My short list would be
Super T10 with Borg Warner overdrive(4 speed with an electric OD)
A833 or MY6 (New Process 4 speed used by dodge and gm with an OD)
NV4500 5 speed (granny low and overdrive)
Tremic or kieseler 5 speed

I would not use
a T5
Muncie M21 or M22 (no overdrive although I have heard the cluster can be changed out to get an OD.
Saginaw
sm420
sm465

My reccomendations are for some of the stronger transmissions with OD, which will be important with the 3.73 gears.

Thank you for the advice. I'm looking for a minimum of 4 gears and I'd like overdrive.

I don't understand why you wouldn't use a Muncie M21, M22, SM420 or SM465. Those are some very stout transmissions and I guarantee they can handle the power.

I have a 427 in front of an M21 in my Corvette and it's a wonderfully shifting piece that works really well. The M22 is a rock crusher, of well-deserved drag racing fame.
The SM420 and SM465 are top loader rock crusher Muncies and are just about bulletproof. I have an SM420 behind a strong 350 and it works perfectly. I've got an SM465 out of a seventies tow truck, but the 420 works so well that I don't really need to change it.

The only reason I can see that you don't recommend them is because of the lack of an overdrive, because it certainly isn't because of strength. You can overdrive a Muncie if you use a Gear Vendors overdrive tailhousing. Then every gear can be electronically overdriven.

Then you're going to spend money.

My vote is for an RPO MY6 (GM 82-86) aka NP A833. Designed for/by Chrysler, run behind everything from slant 6 to Hemi, and everything from Duster to 3/4 ton truck. The MY6 is a side shift 4 speed, it has about the same gearing as the sm420 2nd, 3rd, 4th, for 1st, 2nd, 3rd (1:1) except 4th is an overdrive. You'll need to have a bell housing with or open up to 5.125 for the bearing retainer, and the drive shaft made to fit.

Larry

The last swap meet I went to I saw Muncie 4-speeds starting in the $750 to $1000 range. Tremecs are usually more.

The only transmissions you can buy that will handle any abuse at the power levels you're talking about which won't cost at least as much as the Muncie would be something like the SM420 and SM465, which are also made by Muncie.

If you are committed to running a car-type performance manual transmission you'll have to spend some coin to get a stout one.

If you want an overdrive you'll spend even more. If I wanted an overdrive manual transmission I'd look hard at the Tremec 5- and 6-speed options. I'd expect to spend $2500+ for a new one.

I have a DNE 4+3 which is a Super T-10 with an automatic overdrive. Its a stout transmission that can take some abuse, but it highlights the downside of having an add-on overdrive over having an overdrive gear in your transmission.

If I were replacing it with another manual it would definitely be something like the Tremec. I think more likely though I'm going to trade the car for one with an automatic.

Personally, if the truck is a serious keeper, I'd spend as much money as you need to get the right transmission. In daily driving, lack of another gear or too much RPM ruins the trip for me even more than not enough power.
Close ratios? Very rare to get these in a truck-specific box.
How to tell what you need?
It's mostly how wide your engine's "happy" RPM range is (definitely not peak power), and how fast it must turn to get off the mark.
A highly tuned 250 L6 and a box-stock and tired 350 V8 may have the same power, but the 250 will fall on its face with truck (wide) ratios, and the 350 will almost not care - a Cummins won't care at all.
More cam, bigger ports = closer.

No such animal, unless you make it yourself. The B-W overdrive was only used on 3 speeds.
Also, you no to the T-5, but you suggest the Tremac and Keislers. They are all the same transmission, only difference is the name and perhaps some internal improvements by the later manufacturers.

Maybe he's talking about the 4+3 4 speed overdrive that OldSub mentioned? I used to have an '84 Vette with that transmission.

That could be possible, he wasn't specific. I've seen guys suggest a "4 speed with the B-W overdrive", meaning the old style overdrive instead of the 'Vette trans. Not exactly a common transmission, I think they were only used for 2-3 years, especially considering that there's plenty of better ones out there that are easier to find for less $$$.

I once owned a Saginaw 4-speed with the OD from a Saginaw 3-speed adapted to it. I don't recommend that conversion based on my experience with it, and I'd not recommend trying to adapt the DNE 4+3 from a 'vette to anything else. Frankly if that transmission is ever removed from the car while I own it something else will go back in.

I'm not sure what a T-10 with an electric overdrive is, but there was a DNE 4+1 that I believe is related to the 'vette transmission and perhaps that is what he means? I know little about that transmission except it is designed in such a way it is more swap friendly than the 4+3.

Add-on overdrives, which is really what the 4+3 is, and is what my old Saginaw was, require managing that OD. Even with the computer controlled unit in my 'vette it makes decisions about when to be in overdrive and when not to that I don't always like. I basically have to shift it manually to be in control of the combination. Around town I usually just lock the OD out and ignore it.

The shift from 1st to 2nd is problematic. Effectively its like moving the shifter the same way each time, but not knowing if it will choose 2nd or 3rd. It makes consistent smooth shifting nearly impossible.

I suspect I'd have the same problem running a Gear Vendors OD behind a manual trans too.

If I need to shift manually I'd rather just have a 5-speed or a 6-speed and have a single control (shifter) and a single process for choosing gears.

All things being equal I'd choose an automatic...

DNE 4+1 is now called the Richmond 5 speed. 5th gear is not an overdrive. From what I could find, it isn't really a suggested trans either.

I have heard about, but have not personally done the t10 with OD. I believe the 3 speed OD will bolt up to it, but I have no first hand knowledge.

I understand the tremec and kiesler are t5 based transmissions. They are advertised for 500 and 600 horses. A stock gm t5 would be limited to around 300 hp.

I believe the M21 and M22 to be great transmissions. I didn't reccomend them because of the 3.73 gears, although the truck would motor down the freeway ok, it might be loud. I would think those transmissions would perform well for the 1/4 mile with the 3.73 gears. My choice would be 3.07:1 gears to 3.42 gears without OD.

Again I am not paying for these conversions. I was listing possible suspects so semperfink can do some more research.

Personally, I am a huge fan of the NV4500 and have put one of those behind a well built pontiac 389 in my 59. I also plan to use one behind a well built 302 6 cylinder in my 1940. I had to make my own adapter plate for the 1940, well I guess I chose to make the adapter... could have swapped out bellhousings and used an AA adapter. I am getting off topic here.

Another vote for the 833 OD. They are found with chevy bolt pattern in early/mid 80s pickups. Extremely strong and had a 30 some percent OD ratio. First gear is a little lower than I would like, but OK.

Hey Swingdaddy,

I have been reading up on the NV4500 since you first mentioned it and I like what I've been reading so far.

I did read an article on the NV4500 that said it had problems with 5th gear slipping because the retainer nut would back off over time. The article, which I can not longer find, said this was an issue with "older years" but never said what years those were.

If you are aware of this issue, can you tell me what years this encompasses?

I don't know what years are affected, but I've seen the problem dealt with by simply welding the nut in place to assure it won't back off.

While that seems a disturbing approach the impact is you have to replace that shaft if you ever need to take it apart. And that would not be the end of the world...

However I've heard that with New Venture now defunct parts are getting hard to find. Since we all deal with obsolete parts all the time that may not be a big deal, but I always feel an advantage of updating things like transmissions is access to parts and this transmission may not have that advantage.

I beleive there is an aftermarket part that fixes the retainer problem on the 4500. I will tell you about another problem with them, though, incorrect lube use. Seems that they are very sensative to what goes in them. They call for a full synthetic 50 weight oil, Castrol is the factory fill, and the part number for it is on the right side PTO cover. Anything else will wipe out the syncros, especially regular gear oil.
BTW, there is no direct fit adapter to bolt the 4500 to a 235. That was the first trans I looked into when I got mine. AA doesn't have one for it. You might be able to favbricate something that would work, though.

Thanks Bill,

I did read about the lubrication issue. I'd be sure to use exactly what the factory recommends and I'm planning on dropping in a small block, so won't have bolt on issues.

The more and more I read these comments and read articles, it seems like spending a little extra to get a Tremec 500/600 would be the best choice. I'm on a budget for my build, but I'm not interested in parts that won't last me a long time, so where I need to invest money I will.

I'm still interested in the NV4500, especially since I have a chance of finding one on a truck in the salvage yard.

I have a friend with a World-Class T5 in his 65 mustang. The engine is rated to be 440 HP and he has a 150 shot of nitrous. He has 3.73 gearing in the rear and runs 13's in the 1/4 mile. He swears by the T5, but out of all these responses it doesn't come recommended. Does anyone have reasons why?

Lastly, I found some transmissions shops online that sell "new Muncies." They are not rebuilt, but completely new transmissions. I am assuming they have the rights to the design, but does anyone know if the quality is any good?

Thanks for all the advice Bolters.

I am not sure of the years of the NV4500 that are affected by the 5th gear nut backing off. There is a fix for it and most rebuilt transmissions have the updated nut. I believe it was most common for the nut to back off on the transmissions that went behind a diesel. The NV4500 is a great truck transmission, however I might think twice about racing with one.

You are correct that there isn't a direct fit adapter. There is an adapter that will work with a little bit of machining. The adapter plate is indexed for the later(1968 on) truck bellhousings. Those bellhousings are indexed to 5.125 inches. The 235 bellhousings are indexed to 4.686 inches. Any competent machine shop could chuck the adapter in a lathe and turn down the indexing lip of the adapter plate to fit the 235 bellhousing.

So in summary, the adapter plate is made that will fit the 1948-1967 chevy and gmc bellhousings, but it requires a little work.