new gears or sm465?

[SSC's76]

hi all happy thanksgiving. today I figured I would do some serious planning for the new year and what step to take next on the truck. as of now I have a a 454 in sig runs great but about 2 years ago I trashed another 12 bolt beyond repair and got stuck dumping a 3.08 12 bolt axle in to get back on the road quick. I do admit I love the low rpm highway driving so much the loss of power and minor issues in the city I can live with. I currently have a Muncie 3 speed and its about to need a rebuild. I plan on doing alot more camping this summer and that means towing which isn't bad but some places we go it would be nice to have a granny gear cause getting going fully loaded without using alot of clutch is kinda impossible. back when I had the 373 rear end it wasent to bad but these 308's are a little harder to get going with. so I was either thinking of bundling another axle or going to a sm465 which I can pickup fairly cheap. I don't want an auto and the 5 speeds I can find local either are trashed or they want over 1200 and im sure I would be itching to change the rear end ratio at the end of the day to take advantage of the 5th gear. kinda want to keep it simple and quick. anyone have have opinions either way?


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[86c20]

with the sm 465 your highway wont change if your 3 sp is non od. and then you gain the 6.33ish low gear what about getting a 14bolt with 3.73 or what ever. i have 3.42 and good all around for me. you will play hell braking a 14

[Firebirdjones]

If you keep trashing 12 bolts I think that's the issue that needs to be addressed first. You need to find a good 14 bolt to swap in like mentioned above.

3.73's are pretty common in them, and frankly I find 3.73's a very friendly highway gear, with a 28" tire you can cruise at 65mph at only 2800 rpms. Add an inch to the tire and drop 200 rpms. So going with a 30" tire would knock the rpm down to the 2500 range, which is very acceptable.

If it were me I'd stick with a 3.73 and fine tune the tire height to your needs so you get a good compromise between take off and highway. Then you don't have to worry about swapping transmissions as a bandaid, and you'll have a rearend you would be hard pressed to break.

[SSC's76]

thanks for the replies one major reason I was thinking of doing the trans is the current one is about in need of a rebuild. I was thinking of being nice and putting my 3 speed into the wifes buick dumping the pos Saginaw that's in there now. the reason I broke the 12 bolt was user error lol I think I grew out of that stage of my life and gas is to expensive.


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[SSC's76]

Originally Posted by SSC's76

thanks for the replies one major reason I was thinking of doing the trans is the current one is about in need of a rebuild. I was thinking of being nice and putting my 3 speed into the wifes buick dumping the pos Saginaw that's in there now. the reason I broke the 12 bolt was user error lol I think I grew out of that stage of my life and gas is to expensive.


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oh and I forgot to mention fuel economy on the highway puts most 350's to shame I've been getting about 15 to 17 fully loaded bed bikes camping stuff and towing a pop up camper. kinda another reason the rpm rang I run I love. I hate this this decision


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[Desert1957]

I think the answer to your question is determined by what you are doing with your truck. I have an SM465 with 4.10 gears in my 83 that tows my trailer and camper but its not a performance style manual transmission. Actually the wide gear ratio's kinda suck for normal driving.

If you want to have a "Performance" setup go with a regular 4 or 5 speed trans, The SM465 has such a low first I never use it unless I'm towing.

Desert

[68Timber]

I'm looking for an sm465 for mine and it has 3.08's. My way of thinking is the granny low will make a gear change unnecessary, especially with 4-low available. And 3.08's are good with a 1:1 final drive. 3.73's with a five-speed is much better but also far more expensive. That could run over 2 grand easy versus a few hundred for the 465.
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[86c20]

bruiser is right. i have been looking for a low grear 5speed and there is the nv 4500 but dam they get up there

[SSC's76]

Originally Posted by Desert1957

I think the answer to your question is determined by what you are doing with your truck. I have an SM465 with 4.10 gears in my 83 that tows my trailer and camper but its not a performance style manual transmission. Actually the wide gear ratio's kinda suck for normal driving.

If you want to have a "Performance" setup go with a regular 4 or 5 speed trans, The SM465 has such a low first I never use it unless I'm towing.

Desert

how well does the granny gear work when your towing? this is kinda why I was leaning toward this direction. like I had said above there are certain places we go where 5 mph up and down hill would be perfect. with the 308 gear and current trans I take off and at 15 mph almost instantly. the only thing I've ever owned with a granny low was my old 83 i6 bronco. with that in 1st and 4 low it was so slow it was like going in reverse lol but all kidding aside I could point and let off the clutch and that sucker would climb about anything without even any throttle.


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[86c20]

if you are in 4 lo you are more likly in 2for 5mph the low creeper gear i have in my c20 i can move 20k lbs will slight throttle then in to first gear. now in my k30 with 4.10 gears and sm465 in 4lo wide open it is about 3 mph i get about 25 mph in forth with 4 lo.

i find that no matter what i am doing low gear just to get moving then in ot first

[Firebirdjones]

Originally Posted by Desert1957

I think the answer to your question is determined by what you are doing with your truck. I have an SM465 with 4.10 gears in my 83 that tows my trailer and camper but its not a performance style manual transmission. Actually the wide gear ratio's kinda suck for normal driving.

If you want to have a "Performance" setup go with a regular 4 or 5 speed trans, The SM465 has such a low first I never use it unless I'm towing.

Desert

This is exactly what I was thinking. I got the impression from the OP's first post that he was more into performance with this truck, breaking 12 bolts and all. So the first thing that popped in my head is that the SM465 is not the trans for this, definately not performance oriented. If he's breaking 12 bolts he'll make short work out of that SM465 as well, not to mention the gear spread is horrible.
It's more of a work horse transmission and is not something for banging gears and popping clutches. Great trans for a work truck.

My personal opinion, if you want to set this up right, and you want a manual trans, you are worried about gas mileage, and you also want a lower first gear, and you also like to horse around with this thing,,,,Then you really need to just step up for a TKO600. Very strong trans, 2.84 first gear and a .64 overdrive. With 3.73's it would be perfect in first gear and in overdrive. You get the best of both worlds. Because what you are trying to accomplish otherwise is more than likely going to lean more one way than the other and a compromise will have to be made, something is going to suffer.

TKO retro swaps are made for just about every chassis now and various vendors. Actually swapping one of these in a vehicle that is already a manual trans is relatively inexpensive vs a full blown swap over from an auto.

[Desert1957]

Originally Posted by SSC's76

how well does the granny gear work when your towing? this is kinda why I was leaning toward this direction. like I had said above there are certain places we go where 5 mph up and down hill would be perfect. with the 308 gear and current trans I take off and at 15 mph almost instantly. the only thing I've ever owned with a granny low was my old 83 i6 bronco. with that in 1st and 4 low it was so slow it was like going in reverse lol but all kidding aside I could point and let off the clutch and that sucker would climb about anything without even any throttle.


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It does an awesome job towing, Here is a pic of how much its pulling.

Desert

[SSC's76]

looks like it does a real good job. well Im not sure if I will go this route after all found another option. seems the wifes grandpa decided he shouldn't be driving anymore so it looks like I may be getting his 93 extended cab shortbox. 350 crappy 700r4 and 4x4 which I was looking at getting a 4wd but more like a Cherokee but we will see I do like the extended cab shortbox trucks


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[LONGHAIR]

I would be as concerned about braking as I would gearing on that rig.

[SSC's76]

Originally Posted by LONGHAIR

I would be as concerned about braking as I would gearing on that rig.

that's a good point this 93 has hydroboost which would make it better suited for towing I just need to work out a price with her grandfather and then see what I need to do for my comfort level with it which was the one thing I wasent worried about with my truck since I know my rig inside and out.


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[Desert1957]

Originally Posted by LONGHAIR

I would be as concerned about braking as I would gearing on that rig.

FYI Trailer is a "GOLD RUSH" 100% Aluminum, If your'e not familiar they come with 8 lug 6000 LB axles and have the largest brakes of any trailer of its kind. You can stop the whole rig with just the trailer brake controller.(If you had to)

Truck is a "Camper Special" and is rated for more bed weight than it actually has on it. 1 ton everything. brakes and suspension.

Tows great and has Never felt unsafe while towing or braking.

Desert