Sm465

I have a 1988 chevy k1500 with a sm465 4 speed, been wondering how common are these trucks with that transmission and if I should possibly swap it out with something else in the future or keep it

sm465 old school, bullet proof, really only a 3 speed, with its granny low.
no idea on how common, depending on your use, mostly offroad might want to keep it.
imo, if truck is more of a DD, then it's asking for a 5speed ....

It is my daily, I like it but it definitely feel a little sluggish at times

Good strong trans that was only offered in the first couple years of these trucks. My 89 snow plow truck has one also.

Really easy to swap in an NV3500 or NV4500 to get that 5th gear. if you drive it enough to justify the swap. NV4500s are getting rare to find but if you keep an eye out and aren't in a hurry you can still find one. Look for a 1995 model. 1995 is the last year of the external slave cylinder (easy to swap) and the first year of the 'better' gearing... 1st is a real 1st not a granny 1st like the pre 1995 nv4500s.

RichLo said:

1995 is the last year of the external slave cylinder (easy to swap) and the first year of the 'better' gearing... 1st is a real 1st not a granny 1st like the pre 1995 nv4500s.

Click to expand...

NV4500 early version low gear is 6.34:1, later version is 5.61:1.

NV3500 from a GM fullsize truck 1st gear is 4.02:1, in other applications they were offered with a 3.49:1.

Some of y'all got funny ideas of what a "real" 1st gear is; neither version of the NV4500 gearset has what I would consider low gear being a usable 1st gear for regular driving. For practical purposes it's a 4 speed overdrive... which is still definitely an upgrade over the SM465 if you're driving any amount of highway speeds.

Richard

I had one of those dump truck transmissions in our old '88 C3500 behind a 454. Like others said, it was bullet proof. But that's about all it had going for it. It was so slow to shift and 4.10's coupled with no OD meant something like 2,600 rip 'ems at 60 mph. I hated it. Gave myself a year to find an NV4500 locally before I said I'd sell it. Sold the truck. One of the few vehicles I regret selling. I haven't found a decently clean, one ton, regular cab, long box SRW stick shift truck since, big or small block. I'd love to have another.

could be wrong but I believe 88 was the only year for the SM465 in the GMT400 and in 89 they went to a 5Lm60 5 speed trans then again in 93 they went with the NV3500 in the 1/2 tons that is.. ive been thinking about swapping my 5LM60 out for at NV3500 so ive been looking stuff up for a few months now.. just trying to source a good NV3500 around my area

The SM465 is a great trans especially for serious offroading. I've got one in my crawler (400/465/205/4.56s/37s) and it's amazing.
Only down fall on the street is...
-no it doesn't shift like a corvette.
-The 2-3 gap is a little wide. But he'll is a wide ratio trans so it's to be expected.
-no "over drive" but if you wanna be all OCD and play the gear ratio calculators you can gear your truck to be about were you would be with a 5th gear. Keep in my mind it's an old truck and shifting gears is cool. You gotta get those smiles per gallon not miles per gallon.
-no one will steal your truck cause they almost no one can drive a stick.
- there is such a thing as a ranger over drive. Effectively it turns your 4 speed into an 8 speed. That way you can "split" each gear. This fixes the wide ratio gaps. May cause a slightly slower shifting speed, but if you know how to drive it's no big deal.

You got the more desirable short throw aluminum top plate and 32 spline out put on your truck (if it has the original trans).
Keep on shifting ...alsoNV4500s are over rated.

Any info on headers for a 5.3 swap running a sm465
stock headers hit the slave cylinder cant find any info.
Thanks in advance