Manual transmission ratios

[Tom400CFI]

Having done some "extensive internet research", I have found that there were two ratio options for the NV3500; 2wd "close ratio", and 4wd "wide ratio". Is that true? I'm PRETTY sure that there are more ratio options than that. A 4.3 w/an NV3500? Those have a pretty short OD and a darn low 1st. Does a 305 TBI 4x4 truck have the same ratios as a 350 Vortec 4x4 truck? I don't think it does. Does it?

Reason for asking: I had a wicked awesome, "unicorn" truck for a long time; a '96 xcab, s-bed, 4x4, 350/5 speed, with a 3.73 10 bolt. Best vehicle I've ever owned and I sold it at 300,000 miles and I shouldn't have done that. A friend of mine affectionately knick-named this truck "The Kenworth", because it'd tow my boat like a freith train.
I've tried 4 different trucks to replace this truck, over the last several years and I've been sorely disappointment in all but a early '07 Duramax, which was awesome, but total overkill for my needs. Anyway, the Kenworth was the perfect combination of all options, which resulted in fantastic performance, great fuel economy, and....it drove "like a car" w/regard to power/performance, shifting (gear ratios) etc.

The truck I have now is a '98 same thing, but it has a 305, 12 bolt rear with, I'd guess, the 3.42 gear? The 12 bolt saps power, the gear kills what ever power is left, and the trans seems to have much wider spaced ratios than the Kenworth had, hurting drivability even more; Climbing a canyon I climb to get to work, 3rd gear is too tall, 2nd is too low.

I want to find or recreate the Kenworth. Part of doing that is understanding the NV3500 options/gear ratio's. What light can this forum shed on this? Thanks.

 

[evilunclegrimace]

Going from a 5.7 with 3.73 gears to a 5.0 with 3.42 gears is your biggest problem.

 

[Sean Buick 76]

From what I can tell both your unicorn truck and this one have the same trans gear ratios. It looks like only the dodge trucks and s-10 that have the “close” version. But the first check is your glove box to determine the gear ratio spread of your trans. You will have one of these two codes, see attached:

I’m betting both trucks have the same trans. Your rear end should be identified as well, check your glove box codes for GT-4, GT-5 etc.

Your 305 can perform okay however it will need a 4.10 gear to keep up with what the 350 could do with a 3.73. Find out your rear end gearing 100% and then look for a 3.73 or better replacement. If it’s 2wd that saves time and $.

 

[Tom400CFI]

From what I can tell both your unicorn truck and this one have the same trans gear ratios. It looks like only the dodge trucks and s-10 that have the “close” version. But the first check is your glove box to determine the gear ratio spread of your trans. You will have one of these two codes, see attached:

I’m betting both trucks have the same trans. Your rear end should be identified as well, check your glove box codes for GT-4, GT-5 etc.

Your 305 can perform okay however it will need a 4.10 gear to keep up with what the 350 could do with a 3.73. Find out your rear end gearing 100% and then look for a 3.73 or better replacement. If it’s 2wd that saves time and $.

Super, ^This^ helps. Thanks a bunch, Sean. Now, I just need to find a 5 speed, 4x4, 3.73 10 bolt, 350 with forged LCA's, that is "grandpa's garage queen"! That's gonna take a while. The 305 truck I have now is not a "keeper", for me. Thing is gutless AND gets terrible gas mileage.

 

[Rock Hard Concrete]

All full sized gm trucks got the wide ratio nv3500.

You should have good results by regearing if you didn't want to have to find a new truck. My gmt800 half ton has the 4.3 with 4.10s and the nv3500, and it will tow well in excess of what a half ton should ever pull, so I imagine a 305 would benefit even greater.

 

[Tom400CFI]

Thanks RHC. Knowing that makes selecting any 350/5speed simple. And if everything else is right, I can change gear, and some other things.

No, I don't mind taking my time and looking for another truck. I don't like this one and I never will. It has zero balls. Even at 5000 RPM in 2nd gear? It's got nothing. I could put a 5.10 in it, run 5000 RPM in third gear for similar results....and still have no balls at all, because it lacks:
Torque
Horsepower
It gets horrific gas mileage! Smaller engine (than the Kenworth), tall gear....worse mileage! Way worse -just filled it today and tallied 13.98 mpg. The Kenworth used to get 18 or 19 in the same driving routine.

You know how GM products can be optioned in insanely stupid ways? Example: Remember 3rd gen F-bodies? I had several, one, an '83 Trans Am. "Loaded": Top engine, auto, power everything, t-tops, top end stereo, tilt, AC, top end seats/finishes, full gauges, top suspension/wheels, 4-wheel disk brakes (big deal in '83!), performance axle ratio (3.23 at that time).....and an open differential! W...T....F??? That's GM for ya.

This truck is like that^; x-cab, 4x4, s-bed, 4x4, late/Vortec V-8, 5 speed, the "nice" bucket(?) seats w/the power lumbar and fold down arm rests, over head console, center console, 12 bolt rear w/big brakes (for a 305!?) -sounds GREAT (why I looked at, then bought it)....But then?
F'd up rear gear, crank windows, manual door locks, and the cheapest music murdering stereo GM ever made. Anyway, steel drive shaft and boxed lower arms. Oh yeah, single cat/exhaust, too. Whoever optioned that truck, they got it about 2/3's right....then they blew it, and ruined what could have been a good truck. Truck is worthless and always will be, IMO. I call it the "Granpa truck", b/c all it can do is just "get on down the road". Barely. It's in no rush, it never will be (can't be!), it's super quiet, just...gets along, and that's it.

So? I'm not interested in "saving" this truck at all. It ain't worth it. I'll just keep it for now, for doing basic truckly things like hauling my kid's go kart to the track and back....and just "gettin' on down the road" when it needs to. Mostly, it sits in the driveway. I'll keep looking for that bad-assed unicorn like the one I had before.