Anybody ever installed a newer transmission on an older engine.

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Frankinmetz

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Has anyone ever installed a 5 or 6 speed to an old carb. Chevy 350 big block?

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Camar068

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I'd like to find a 350 diesel and be able to AFFORD to convert to gas and de-stroke it :)
 
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jjester6000

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Has anyone ever installed a 5 or 6 speed to an old carb. Chevy 350 big block?

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The bellhousing pattern for most GM engines has been the same since 1955, so swapping in a newer transmission should be no problem.

If I were you, I'd pick up either an NV3500 5 speed (easier to find, and actually came in trucks) or a T56 6 speed (Expensive, and never actually put into trucks, but it has one extra gear)

If you are going for the Nv3500 route, I'd find a later, 88-98 GMT400 parts truck with a 5 speed and swap all the parts over (Clutch pedal, lines, Exc.)
 

Frankinmetz

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The bellhousing pattern for most GM engines has been the same since 1955, so swapping in a newer transmission should be no problem.

If I were you, I'd pick up either an NV3500 5 speed (easier to find, and actually came in trucks) or a T56 6 speed (Expensive, and never actually put into trucks, but it has one extra gear)

If you are going for the Nv3500 route, I'd find a later, 88-98 GMT400 parts truck with a 5 speed and swap all the parts over (Clutch pedal, lines, Exc.)
That was the exact answer I was looking for!! [emoji120][emoji120][emoji120] Thank you.

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Frankenchevy

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I’m not sure that you can swap over gmt400 stuff directly. If you want a direct swap hydro clutch pedal, you are better off finding a hydro pedal assembly from an 85-87. It’s $$$, but everything else is going to require some level of fabrication.

I believe the gmt400 stuff is also passenger side throw out and uses a hydro TO vs a slave cylinder. That’s usable, but you’ll need longer hydro lines if I recall correctly. In other words, I think the trans itself, excluding the bell housing, is the only direct swap. The bell housing swaps, but again the clutch stuff is on the passenger side.
 

Ricko1966

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Yes we have installed newer transmissions on older engines, we've installed older transmissions on newer engines, we've even installed engines and transmissions from different makes. We own Chevys damnit !!
 

bucket

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Yes we have installed newer transmissions on older engines, we've installed older transmissions on newer engines, we've even installed engines and transmissions from different makes. We own Chevys damnit !!

Yep! I'm sure there's people running 4L60e's behind their 283's and there's people running a Powerglide behind their LS engine. There's even a member here that's running a modern Jeep 5-speed behind their 250 inline six.
 

JustJohn

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Have a TKO500 on my 454 in the Impala, bolt patterns are the same for all of them (SBS, BBC). I had the OE clutch linkage. If that's not available, lots of kits to add a hydraulic clutch are available.
 

nujac

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I swapped out a turbo 350 with a NV4500 about 10 years ago. I do not know if in 1979 K15 automatic trucks rear ends had a higher ratio than an automatic. Was very pleased with the swap getting another 4 or 5 MPG but the rear end ratio is too high to use 5th gear.
 

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