Author Topic: Tranny choices for 78' K10  (Read 2525 times)

Offline frontlinetrainer

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Tranny choices for 78' K10
« on: July 15, 2016, 02:55:12 PM »
Current parts truck has a SM465 but I'm thinking she'll be screaming at 65+...my current driver is a 2wd SM465 and she screams at 60mph.  Looking for suggestions on a good highway driving manual tranny to bolt up to my 78' K10 with 350.  Thank you in advance!

Offline zieg85

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Re: Tranny choices for 78' K10
« Reply #1 on: July 15, 2016, 04:11:15 PM »
They will all scream unless you upgrade to an overdrive transmission or re-gear higher or go increase your tire size a bunch...
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline winky

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Re: Tranny choices for 78' K10
« Reply #2 on: July 15, 2016, 09:12:17 PM »
we put a 5 speed out of one of my 90s model parts truck in an 82 one time, had to get the hydraulic pedal set up

Offline Irish_Alley

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Re: Tranny choices for 78' K10
« Reply #3 on: July 16, 2016, 07:56:30 AM »
tires will also help with the final ratio, if you can go big enough. but whats your rear ratio it shouldnt be too bad being only a k10.
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Offline roundhouse

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Tranny choices for 78' K10
« Reply #4 on: July 21, 2016, 10:03:37 AM »
The NV3500 five speed from a 97-07 is a nice easy swap
you will have to use a hyd clutch pedal or drill a hole in your clutch pedal arm for the hyd cylinder

We used the stock hyd cylinder
Line it up and drill The big center hole
Then use the cyl as a guide to drill the other two holes
I used all thread rod so we could space the cyl away from the firewall  to get the right distance and a reservoir from any vehicle will work     Think we used a Honda or Mazda

We made our own because hyd clutch pedals are gold now
I've seen people asking $300 for em

If your clutch pedal is worn out at the top pivot so bad that new bushings won't fix it
You can use a brake pedal from an auto Trans truck , cut off the bottom 1/3 , flip it over and bolt the bottom 1/2 of your factory clutch pedal to it
Your factory clutch pedal is in two sections bolted together  so this repair is easy


You mentioned K-10, that's a 4WD
If so

And you will have to swap the Transfercase for a 32 spline NP208 from behind a TH 400

Otherwise get a tach and see exactly what your rpms are
Might not be as high as you think

Larger tires is an easy way to bring down the RPM

33's will fit with no lift


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« Last Edit: July 21, 2016, 10:10:48 AM by roundhouse »