SM465 to 5 Speed Question

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msjulian

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I have a 1987 R10 5.7 with a SM465. I really want to go to a 5 speed to get an overdrive. I really have no need for a granny low in this thing. It is bone stock and completely unmolested with 86,000 miles.

I have search through the posts and most of what I have found is relating to 4x4 swaps or auto to manual and vise versa.

What would be my best option for an overdrive with the fewest mods??
 

DoubleDingo

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Perhaps an NV4500.
 

bluex

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That still gives him the granny low though an a Trans that shifts like a truck. Being yours is already a hydro clutch a nv3500 would be your best option if you won't be towing heavy or trying to make 500HP.
 

msjulian

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I was looking towards the NV3500 as I am planning on keeping the stock 5.7L in the truck. Maybe throw a cam, headers and high flow exhaust at it. I won't be towing any more then a utility trailer with light loads. I just didn't know if that was an easy swap and what inherent issues those transmissions have.

The plan is to get with Ridetech and put their front and rear suspension on, throw some torque thrust wheels at it and just have a nice, cool old truck.
 

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msjulian

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What years would have the cable drive for the sped??
 

Stewzer55

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I don't think any years of NV3500 had a speedometer drive cable. The NV4500 does not shift like a 465, but its still a truck transmission.
 

HotRodPC

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For the 2wd, I don't think it's all that bad to do the NV4500. If a 4x4, it gets pretty expensive to do the NV4500 swap. If it were 4x4, then the A883 if you could find one should be an all bolt in swap, using the same driveshafts, crossmember and all.
 

msjulian

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The NV4500 didn't really cross my mind before. I really don't care if it shifts like a truck. In fact, with what we are doing with the truck I kind of like the "truck shift". Will the NV4500 bolt up to the SM465 bell housing?
 

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I just read up on this the other day but then I started reading about other conversions too. I think it said the bearing retainer on nv4500 is bigger. Check out high impact website, they have most if not all the info you need for the conversion. With you already having a manual transmission, you are already ahead of the game.
 

HotRodPC

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Pretty sure DD is right on that too. You can use a NV4500 Bellhousing, or take the current SM465 bellhousing to a machine shop and have it opened up a bit. Seems a couple members on another forum did that and it worked fine.
 

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There is one that would (or should) be an extremely simple swap, but it would not be the strongest option. A T5 trans would bolt to the stock bellhousing, you would just have to swap the clutch to a 26 spline unit. I just don't know where the shifter would poke through the floor, but it must be in a usable spot because T56's have been swapped in.
 

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No T5 is as strong as an NV4500, you will have to modify your driveshaft for the NV4500. wish I had gotten an NV4500 instead of the T5 just for the safety margin strength wise.
Bob
 

HotRodPC

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What years would have the cable drive for the sped??

I'm pretty certain that Speedo went electronic in 89. So 88 and older are still cable op speedos.
 

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