cummins conversion info needed

[bignbad]

I am thinking of a 6bt conversion I want to use my sm465 and my np205 and a gear venders od that I have. Does anyone know where I can get a adapter to mate the sm465 to the cummins? And can I use my current braking and power stearing ? I see a lot of guys going with the hydroboost set ups. And I want to add vintage air down the road. Do I still order a kit for 67-72 trucks knowin its gonna have a cummins in it. I know I got to box the whole frame for the cummins, atleat a 12in clutch. I really don't want to by a new trans n transfer case.

[Vintage Windmills]

Originally Posted by bignbad

I am thinking of a 6bt conversion I want to use my sm465 and my np205 and a gear venders od that I have. Does anyone know where I can get a adapter to mate the sm465 to the cummins? And can I use my current braking and power stearing ? I see a lot of guys going with the hydroboost set ups. And I want to add vintage air down the road. Do I still order a kit for 67-72 trucks knowin its gonna have a cummins in it. I know I got to box the whole frame for the cummins, atleat a 12in clutch. I really don't want to by a new trans n transfer case.

This is something I'm interested in as well. I've read the main thing you'll want to do is source a larger input for the Sm465 out of a medium duty truck. I think it would then be a decent setup. The gearvendors would really fill in the wide ratios on a SM465 nicely. There are adapters out of breadvans for an auto chevy but I'm not sure if they would work with the manual transmissions. I would think so since all chevy transmissions bolt to all chevy engines, right? The breadvan adapter does have a slight rotated so your engine or trans will need to sit at slight angle.

There are probably aftermarket adapters but I'm not sure how much they cost. Have you looked at advance adapters?

I'm no expert. Many guys will tell you to go nv4500 but the problem with them is they need 5th gear fixed, are expensive, and you need a 50 ton press to rebuild them or have to pay someone to rebuild them. They do have a better shift feel though. I like the G360 personally based on what I've read and seen since they are easy and cheap to rebuild and seem to last if you put an extra quart in to keep them cool.

I've read the 10 spline on your NP205 may be the weak link, if you have turned up the cummins or are using 4x4 much. May want a higher spline count if so, and at that point, you may as well just get a g360/np205 combo.

[Dieselwrencher]

An adapter to use a chevy bell housing is $795 give or take. How much torque will that gear vendors OD take? I agree with Jud, that tcase probably won't live long with the small input. For the money you'll have getting the SM465 and gm NP205 behind it, I would just use a NV4500 and a 29 spline dodge NP205. Or find a round pattern 32 spline GM 205 and swap inputs. Either way you're spending money so really the decision is yours. The NV4500 is a great trans and it isn't hard to repair the 5th gear problem. I've rebuilt them without a 50 ton press. Jud, are you thinking of the NV5600? It requires a 50ton press and I haven't rebuilt one due to that. NV5600's are just plain expensive. But I'd still rather have a NV4500 or a NV5600 before I'd use a SM465 behind a cummins. If you plan to have a real mild truck, boxing the frame is not necessary.

[bignbad]

Gear venders says there units are rated for 1500 plus of torque. yea i know about the shafts for the 456/205. i was pricing nv4500 i found there ranging from 2k to 3k. 2k for just the trans and 3k for the kit plus the trans. I think it would be cheaper to replace the shafts and find an adapter. I have 2 sm465 and 2 nop205s i don't think i need to buy anther trans or transfer case i gladly trade someone. As for as boxing the frame what needs boxed? I read somewhere that you can use a bh off of a nv4500 to use with that sm465 to an 6bt. i just don't remember where i readed it and what need to be done with it as in mods

[brimc]

I'm not sure from reading this but do you already have the Cummins?
If not you could get a complete truck with the 12valve and get the transmission and transfer case and most everything else needed for the swap for not much more than 3 or 4k up here anyway. Would just be completely rotten.

[Dieselwrencher]

Originally Posted by bignbad

Gear venders says there units are rated for 1500 plus of torque. yea i know about the shafts for the 456/205. i was pricing nv4500 i found there ranging from 2k to 3k. 2k for just the trans and 3k for the kit plus the trans. I think it would be cheaper to replace the shafts and find an adapter. I have 2 sm465 and 2 nop205s i don't think i need to buy anther trans or transfer case i gladly trade someone. As for as boxing the frame what needs boxed? I read somewhere that you can use a bh off of a nv4500 to use with that sm465 to an 6bt. i just don't remember where i readed it and what need to be done with it as in mods

I can't help you on the BH. For a mild hauler build, I can't say any part of the frame NEEDS boxed. It can't hurt to do the front portion to behind the front leaf spring shackles. I've done quite a few GM's and none havd frames boxed. 1 was a C30 and 2 K20's. These were late 70's -mid 80's trucks. All were all raggy work trucks and still are. And $3000 for a NV4500? Those people are higher than a giraffe's A_ _ (Tail) I've seen good used NV4500's bringing $850, the bell and adapter are another $400-$450, the 29 spline dodge NP205 $500-$800. Just for references. If you want a price for a brand new NV4500, PM me. With a core, it's half of your $3k and it's all new.

Is your gear vendors OD the one that goes on the front of the trans, or after the tcase?

[bignbad]

gear venders unit goes behind the transfer case. thought of going the route of buyin a complete truck 92-97 ram but everyone around here want 8-12k for them. MY buddy has a 97 6bt laying around he had it for few yrs tryin to talk him out of hes into those jeep Cherokee n he need $$$ so thought about waving a few hundred in front of him n see if he bites.

[Dieselwrencher]

$8-12k is nuts isn't it? My brother's 97 2500 4x4 5 speed with 220k books for $10500. Crazy. However, if you keep a keen eye out, they pop up a lot for under $4k. The gear vendor you have would work fine. So if you did an input swap on the 465 and got an adapter plate, you may be able to be in business. Just keep your engine near stock.

[Vintage Windmills]

Originally Posted by Dieselwrencher

. Jud, are you thinking of the NV5600? It requires a 50ton press and I haven't rebuilt one due to that. NV5600's are just plain expensive.

Oops, yep, shows how much I know

Originally Posted by bignbad

I think it would be cheaper to replace the shafts and find an adapter. I have 2 sm465 and 2 nop205s i don't think i need to buy anther trans or transfer case i gladly trade someone. As for as boxing the frame what needs boxed? I read somewhere that you can use a bh off of a nv4500 to use with that sm465 to an 6bt. i just don't remember where i readed it and what need to be done with it as in mods

Keep me posted if you find a place for the input on the 465 as I wouldn't mind using one behind a mild cummins hauler. I havent looked to hard for the shafts but assumed it would have to out of a medium duty truck.

Originally Posted by bignbad

around here want 8-12k for them.

Just get a rusty 1st gen with getrag and the right np205 if you're going to buy a whole truck and don't want to spend more than 4k

Originally Posted by Dieselwrencher

$8-12k is nuts isn't it? My brother's 97 2500 4x4 5 speed with 220k books for $10500. Crazy. However, if you keep a keen eye out, they pop up a lot for under $4k.

Ryan, 4k for a 2nd gen 4x4? I've been looking for 2 years around here and haven't found one yet, just 1st gens.

[seth7843]

Have you tried looking for a 6bt from a school bus? I know some Blue Birds used to have the 6bts. It will most likely not have a transmission that you can use but you might be able to save enough on the initial purchase of the bus plus scrapping the rest? School busses come up cheap on auctions on all the time.