5 speed gmc transmission , will it fit?

[jonzcustomshop]

I was talking to an old salvage yard guy about my gmc 4000 series, he mentioned that if it had a 5 speed that Icould bolt it into my 1/2 ton..
so I checked and it is the np540go14! thats the 5 speed overdrive!
I copied some info from the www.6066gmcguy.org/ website on it

anyone hear of bolting one of these into a 1/2 ton with a sbc?

************

5-Speed Transmissions
GMC Used New Process, Clark & Spicer 5-Speed Transmissions in the 4000 series & bigger
Trucks. The New Process NP-540 series of 5 speed transmissions came in a few different models.
The "GL" is Pictured below & the others will look the same. The "GO" was an overdrive model,
the other models just had some different gear sets in them for the lower gears, see charts below.
The NP-450-GL was mounted behind a 401M in a 1963 4000 model, not stock running gear
for that truck, you will note that the trans top cover has a back up light switch, which came
out in 1967. This trans will be used in my 1965 GMC 1 ton with the 401M for power.





Transmission Specifications
GMC Used the follwoing Four & Five Speed transmissions.

Manufacturer Transmission 1st
2nd
3rd
4th
5th
Rev
Oil Capacity




General Motors/Muncie SM-465 6.54:1 (this is the one in the truck now)
3.57:1
1.70:1
1.00:1

6.54:1
6 pints


New Process 540GO14 6.05:1 this is the 5spd od in my gmc 4000)
3.31:1
1.84:1
1.00:1
0.82:1
6.86:1
10 pints

[Corts60]

I'm not sure about mounting it but that would be awesome!

[1962k20]

I dont know if it will fit easily. But I like the idia!

[padresag]

I used one of those in my 4 x 4 panel for 18 years.I found the split between 3 and 4 to be to great esp if you are pulling a load I pulled it when i took my detroit out of it. I felt that it was to much trans for a 283. I put a t5 behnd the 283 and if it doesn't work then i will go for an upgraded one or a 700r4 which I have ready to go in. I ran an independent np205 behind it
the shift pattern is also different as when you go from 3rd, you usually go up and to the right for 4th though on these you go to neutral and then drop back down for 4th and then up for 5th
i never had any oroblem with it . it is a good heavy trans. you would never hurt it behind a sb. it has a much bigger input shaft
if you want any measurements give me a holler and I willl get them for you as it is still waiting outside to get shipped
ron

[MacAttack]

Trust me......

[jonzcustomshop]

Originally Posted by padresag

I used one of those in my 4 x 4 panel for 18 years.I found the split between 3 and 4 to be to great esp if you are pulling a load I pulled it when i took my detroit out of it. I felt that it was to much trans for a 283. I put a t5 behnd the 283 and if it doesn't work then i will go for an upgraded one or a 700r4 which I have ready to go in. I ran an independent np205 behind it
the shift pattern is also different as when you go from 3rd, you usually go up and to the right for 4th though on these you go to neutral and then drop back down for 4th and then up for 5th
i never had any oroblem with it . it is a good heavy trans. you would never hurt it behind a sb. it has a much bigger input shaft
if you want any measurements give me a holler and I willl get them for you as it is still waiting outside to get shipped
ron

sounds great, what do you do about the bigger input shaft?
do you have to get a custom clutch disc built foor it?
other than that I should be able to bolt it to my 283 belhousing?
I would love to have 1 more gear, then I might be able to go 65-70 on the highway!

[padresag]

a 400 sbc used the same setup in a 4 or 6,000 series( would have more than likely used the same clutch setup whether or not that it was a NP--clarke or spicer etc would maybe have used the same size input. it will also hang there the same way that the stk trans did, just off the bellhousing. it should take a 1410 ujoint so you will have n/problem there as you can get a conversion joint which will match what you already have
Jolly has a 400sb sitting there in his yard with bellhousing flywheel ,everything that you would need which he may depart with separately. He did want $500.00 for the unit awhile back(eng and I imagine b/hoousing and clutchh assy would be inc but may be persuaded to depart with the clutch assy alone.
Jolly is driving truck now but I think that he chks his email
ron

there are quite a few people looking for that trans so they bring a good $ on the market

[Corts60]

Originally Posted by jonzcustomshop

I would love to have 1 more gear, then I might be able to go 65-70 on the highway!

I know how you feel....

[padresag]

NP 5spd meaurements
the input shaft is 1 1/2"-10 spline----pilot bushing shaft size is 1" on the od
frt mounting bolts across c-c 81/4"--top
bottom across 9 1/4"
I think that they are the same measure as a sm420
frt brg cover 5 1/4" dia
ron

[jonzcustomshop]

thank you for those measurements, now I have to get to work building something to put it in!!

[jonzcustomshop]

I just found another one of these trannys, has the same shift pattern as mine, but it is in a chevy COE is there a way to change the shifter to one that work in a regular truck?

['63GENIII]

I don't know about the shifter but I do know that those things are virtually indestructible. I had one in a 57 Napco 1 ton utility bed truck years ago. Oh yeah, they are REAL heavy too! Hope it works out for ya. I'd love to have another one in my '63... vintage O.D.!

[padresag]

you should just be able to change the top cover to a conventional one
ron
you just have to find one

[jonzcustomshop]

thats what I was worried about, conventional 5 speed right?
I'll just have to come up with some sort of mid engined truck so I can use this tranny with the coe shifter

[padresag]

that I show you want to use it,isn't it. like a conventional. you just have to look for a clapped out tranny for the shft tower and with the top plate and your away. same trans , just different shifter
ron

[jonzcustomshop]

not sure I follow? would the shifter tower and top plate off a 4 spd work? I have plenty of those...

[padresag]

the coe doesn't have the std shifter on it so you would have to get one off another 5 spd(conventional). those 5 spd have a different shift pattern. 3 and 4 are reversed. mine did anyway
ron

[jonzcustomshop]

...might just buy it to have in case something happens to the one I have then...you never know , might find a clapped out 5 speed down the road...
thanks for the info!

[292farmer]

did u mount the 5 speed in your 1/2 ton? thinking of doing it in my c20. thanks

[jonzcustomshop]

haven't yet, but might be getting to it later this year.

[292farmer]

well i guess we'll see who gets their first lol btw this might help you maybe not his is the gl but i believe the cases are the same just the internals are different(im still researching)
http://www.bethsbackyard.com/NP540GL...escription.htm