sm456 swap. questions

[bmwallace_88]

dont flame me to bad if this has been covered, but i have a 78 4x4 1 ton with the sm456 and was wondering if there was a 5 or even a 6 speed i could put into it, has the 454/sm456/205 right now, was wondering if there was a different trans that wouldnt cost me 3000-4000 to swap, looking to do it on the cheaper side, bought the truck before gas hit 4 bucks a gallon, and now i'm regreting it, getting 6 mpg isnt cutting it. lol if there isnt a swap, guess i'll just cruise it the way it is, i'll never get rid of this tank, i love it. but want a different trans, any options, i was reading about the t56?? worth it? lemme hear some of you gurus opinions, thanks in advance.

[old school truck dude]

Go to an automatic with overdrive

[bmwallace_88]

nahh, i wanna keep the stick, no way would i get rid of that, reason why i bought the truck was the manual 4x4 dually camper special crew cab and rust free is a kicker, but anyways, i wanna keep the manual trans.

[7387chevynut]

nahh, i wanna keep the stick, no way would i get rid of that, reason why i bought the truck was the manual 4x4 dually camper special crew cab and rust free is a kicker, but anyways, i wanna keep the manual trans.

I understand where your coming from, but you have to look at the simple facts of reality.

you have to remember what you (have)..........a 1 ton K30 truck...............that was never made with the intensions of getting (good) gas mileage...........and certainly not with a 454 either.

If you want good gas mileage then swap out those 4:10 or 4:56 1 ton axles and slide some 2.73 ratio 1/2 ton axles under that truck and drop a 250 straight six under the hood.................then you'll notice a improvment in gas mileage.

You could also buy a small car to drive.......................but either way there is no (cheap) way to solve your problem.

Also your trans is a SM465....not 456. GM did offer of rare oddball New Process A833 4spd OD manual trans hooked to the NP208 found in some early 1981-up GM 4x4s, but they arent strong compared to the SM465......and were never offered in 1 ton k30's and I am not sure if it was ever offered behind a 454 even in a 3/4 ton truck.

[old school truck dude]

Actually, 6mpg is pretty good.. I seem to recall them only gettin about 4mpg

[bmwallace_88]

If you want good gas mileage then swap out those 4:10 or 4:56 1 ton axles and slide some 2.73 ratio 1/2 ton axles under that truck and drop a 250 straight six under the hood.................then you'll notice a improvment in gas mileage.

wouldnt it be easier to go buy a new colorado or canyon? lol, i'm not asking for 20 mpg

this isnt my daily driver, and im not LOOKING killer good gas mileage, but i plan on keeping this truck, and dont want to keep it at 6mpg, everyone is acting like i'm asking for 20 mpg out of this rig, honestly, if i got 10 i'd be happy, and i dont mind spending money on it, as i said. 3-4k is what i'm looking at spending. i dont want to get rid of the car. i have a nice CAR to drive, but you dont see these everyday. personally it isnt bad, and it doesnt have to be really strong, its not like its going off roading, or even towing for that matter, just purely a hwy driver. just looking for some tips to save really. and i'm having griding problems with the 3 spd, and the crawler gear is completely pointless, at 3 mph i'd rather have more uptop than down low

[4x4xdodgeman]

put overdrive unit in the truck. call Gear Vendors under/Over drive unit.

[bmwallace_88]

i was looking around at those being a viable option as well, and they are within budget for sure.

[RIP_K52007]

turbo & a nv4500

[cnoswalt78]

Also your trans is a SM465....not 456. GM did offer of rare oddball New Process A833 4spd OD manual trans hooked to the NP208 found in some early 1981-up GM 4x4s, but they arent strong compared to the SM465.... exacly chevynut my dad had several not very strong but cheap way to go. look like a saganaw 4 speed and about as strong! od auto is the only cheap thing. but supose you could put a brownie in it (anyone tryed it)

[old school truck dude]

Also your trans is a SM465....not 456. GM did offer of rare oddball New Process A833 4spd OD manual trans hooked to the NP208 found in some early 1981-up GM 4x4s, but they arent strong compared to the SM465.... exacly chevynut my dad had several not very strong but cheap way to go. look like a saganaw 4 speed and about as strong! od auto is the only cheap thing. but supose you could put a brownie in it (anyone tryed it)

Brownie box is for makin even lower gears, its basically just an extra granny gear transmission, has yokes on front and back.. great for a big truck like a well-drillin rig or rock crawlin, but probably not something for gettin more mpg

[ice87]

Switching it to a TBI set up would be a good idea if its stilla stock motor. My buddy had a 1988 crew cab long box dually 454/400/208 on 36 TSLs. He got 10 MPG with an automatic and still had great power. Alot of people don't like fuel injection but it does have its perks.