Which tranny should i run?

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HotRodPC

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Around here the NP205 is the Gold, so they sell for $250-$500 depending on if they are fresh or not. Usually about $250-$300 for used and working and thought to probably be original. But the Th400 is usually a ride along for free with the NP205. If I had $200 I know I can have a good working Th400/NP205 Race Track pattern right now, all married up with adapter and NP205 shifter included. I've got the Th350/NP205 with shifter, and adapter all married up that I got out of that kids 80 K10 so I figured I"d go Th350/NP205 and cash being so tight, I can't justify the $200 to be spent even though I'd love to have it for just because.
 

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Guys, for what he's doing with the truck, a set of 4.10 gears, a trans cooler, and some preventative maintenance to the trans will make the truck plenty reliable, and be better than just ditching the 700r4. A simple 3/4 ton able swap to a set of axles that already have 4.10s in then it's way closer to a16 year old's skill set than setting up gears. Plus it will be a strength upgrade, as well as being far cheaper than gears and proper install kits for both axles.
 

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That would be the good option, and try to get the driveshaft from the donor truck too if you found the axles, then it's all a turn key bolt in job. But then he'd also need wheels and tires.
 

1973 Chevy

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That would be the good option, and try to get the driveshaft from the donor truck too if you found the axles, then it's all a turn key bolt in job. But then he'd also need wheels and tires.

Good point with new wheels, the new gears or new wheels might offset each other with the price. But then ill have heavy duty axles, plus I think theres something broke in one of my front locks right now. I got time to decide.
 

HotRodPC

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Good point with new wheels, the new gears or new wheels might offset each other with the price. But then ill have heavy duty axles, plus I think theres something broke in one of my front locks right now. I got time to decide.

If you're planning a gear change, I'd certainly agree with GD on that upgrade. And then you're getting used axles that you can be fairly certain were set up right. Not always, if some idiiot got in there and did it, but usually 14b Full Floats don't break for example and go forever and ever. So you found a FF and a Dana 44 or 10bolt Front out of a 3/4 ton, strong chance they are 4.10's and a chance they could be 3.73. Either of the 2 gear ratios will be good, 4.10's preferred since you have the OD and likely to run bigger tires. I've seen a set of used 3/4 ton axles anywhere from $250-$500. $300 and $350 are pretty common. Lately though, seem they are closer to the $500 mark. Buying these truck parts is a matter of timing. Anyone will tell you, I've not spent to much for a damn thing on my trucks and parts. And most of what I bought, I wasn't looking for, in fact none of it. I just bird dog CL and when I see something to good to be true, pounce on it before someone else does, or before someone educates them about it.

But, do try to get the rear driveshaft form the donor truck. Yours is long bed right? 3/4 tons didn't come in short bed, so if your long bed and the 3/4 is long bed, you'll have the right one to match the 14b FF length difference, and not have to use a combo u joint, and have a stronger driveshaft too. Usually, the driveshaft can be a deal sealer. Tell the seller if he has it, you'll take it IF he throws in the driveshaft. Most don't give a rats ass. On that A833 trans I bought, I had that guy throw in the front driveshaft and crossmember. He didn't even flinch, and said yeah, I don't need it. Save me a bunch of time hunting those parts down and buying them. (Although I had them already and didn't know it).
 

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The driveshaft will only be right if the donor truck has the same trans, transfer case, and adapter combo as his truck. I've never had issues with stock driveshaft length on a 14 bolt swap.

A lot of people will tell you a 3/4 ton swap is worthless as a strength upgrade, and the are correct. You get bigger brakes for your bigger tires, and a lug pattern and hearing that matches your upgraded rear. The front axle won't matter much. If you break a shaft, our even lunch a ring and pinion, unlock the hubs, shift into 2wd, and drive home. The rear is wherethe added strength is needed. No need to stick specifically to the ff, a semi float 14 bolt will do just fine on 35s.
 

1973 Chevy

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Found an add on c-list with a TH350 bolted to a NP205 and the t case has the rear attached yoke - $300. Then in the same add a TH350 with a NP208 - $150. Thats all the information I got, haven't called him up yet and its not a 1000 miles away.
 

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NP205 is the best way to go, but find out what year the trans is out of. 80 & up is TH350C which means lockup converter, somewhat less desirable.
 

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I learned that its a 1972, so will that just bolt right in on my '86 frame?
 

crazy4offroad

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I cant say for 100% sure, if there were some pics, especially of the mount I could be more sure.
 

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I cant say for 100% sure, if there were some pics, especially of the mount I could be more sure.
He's sending over pictures tonight so ill get him to snap a picture of the mount.
 

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It will bolt right in, but I don't know what crossmember you would use since you have an '86 frame. I think your current crossmember and mount will work though. The earlier 205's had an additional mount that bolts to the passenger side frame rail, you don't need to use that if you don't want to.
 

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Everything in this photo is what the deal is, I got bad eye sight but isn't that a cross member already on there?
You must be registered for see images attach
 

HotRodPC

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I don't think year model of the truck matters. Think what matters is the adapter you use. Use the Crossmember that goes with your adapter. Usually either short or tall. Short adapter goes with the W crossmember as in the later models, then the Tall adapter goes with the early crossmember if I've figured that out correctly. I think I have pics of both. I'm using the older style crossmember with my A833, which is good cuz I have 2 of the older crossmembers, and need the W member for the other truck that's being used in the K1500 right now.
 

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