700r4 blown. Nv3500/4500 swap

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roundhouse

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Isnt there a nv3500 in the s10s? 32 spline seems overkill for an S series.
The 3500 in the S-10 won’t fit

Think it has a differentbellhoising bolt pattern

Also the pattern for the transfer case is different



The 3500 is a 32 spline
Needs a NP208 from behind a late 80s TH400 with the round bolt pattern

The 208s came in figure eight bolt patterns with two or three different splines , and in circle bolt patterns with 27 or 32 splines

When you’re shopping for one , do NOT trust the seller
They will lie to sell it
Count them yourself
Or ask them to send you a good quality pic of the splines

And get the crossmember support if you can

And ask for a pic of the t case
I’ve driven an hour to buy a 32 spline 208 and found the diphead seller had a NP205

I would try to drive a 465 in someone’s truck before you swap one in

They shift really slow and the ratios are way far apart

I like the 3500
It’s the closest you can get to a car transmission in a pickup

I’ve had a stock 3 speed and T-18 in my bronco before the 3550 in my bronco

And a 465 in the K10 before the 3500

And there is a huge difference in drive-ability on the street for a daily driver
 
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bucket

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The 208 used in GM trucks only came as a round pattern. It was introduced in '81. It's often overlooked that the round pattern 27/32 stuff came out that early because everyone's focus is always the K30 which didn't get anything round pattern until '85. Through '84, they retained the figure eight 205 with 10/32 splines.
 

guitarfreak235

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Lots of good info. I found a rebuilt 700r4 with a new torque converter for $300 and just snagged it. 20k on the rebuild so sounded like a good deal cuz tranny shops are all asking for 900 plus per rebuild.

Im putting that in for now, and might just assemble the required parts for the manual swap when im not in a hurry

Sent from my SM-G920V using Tapatalk
 

HotRodPC

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SCORE !!! So long as it's really a good one, I'd certainly use it for now. Now that you have some ideas and know what to keep your eyes open for, then maybe beforre that one goes **** up you'll have acquired your parts for the conversion.
 

mcarlo86

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We are considering a NV4500 swap into our 90 V1500. I have a line on a good 4500 out of a 94 4X4 Chevy pickup. I also have a parts pickup '77 K20 with a 465 transmission in it. I'm wondering if the clutch pedals would work out of that pickup for the swap? I have seen that AA sells a NV4500 bellhousing for mechanical clutches so I wouldn't need the slave cylinder, master cylinder, etc. Has anyone had experience with one of those? I'm not positive on what t-case I have, but I think it is a 241? Would this t-case work with a NV4500? How about making it work with the factory cruise control?
 

SDJunkMan

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I found a 96 with a 4500 in it for a good price, wondering what else I should get off it (pedal assembly, bellhousing, etc.), that I would need to swap it into my 78 K10 with a 465.
 

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I found a 96 with a 4500 in it for a good price, wondering what else I should get off it (pedal assembly, bellhousing, etc.), that I would need to swap it into my 78 K10 with a 465.

Other than the trans not much else is going to swap over. T-case output is on the wrong side (IFS), bellhousing won't work without major mods and the pedal assembly is completely different.
And...if you drain the oil and it's conventional gear oil, your going to need an overhaul to replace the carbon synchros.
Save yourself the headache and get comfortable spending big$$ on the AA bellhousing and slave cylinder bracket. It's still worth it in the end.
 

SDJunkMan

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Other than the trans not much else is going to swap over. T-case output is on the wrong side (IFS), bellhousing won't work without major mods and the pedal assembly is completely different.
And...if you drain the oil and it's conventional gear oil, your going to need an overhaul to replace the carbon synchros.
Save yourself the headache and get comfortable spending big$$ on the AA bellhousing and slave cylinder bracket. It's still worth it in the end.
Thanks Mike. I would have hated to left something on the truck and found out later that I needed it.

I am wondering if I should pull the tranny and transfer case as a unit or can I split the transfer off first? I've never split one before, but I'm getting too old to be wrestling the pair if I don't have to, not to mention that I will have to split them eventually.
 

Dutch Rutter

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Thanks Mike. I would have hated to left something on the truck and found out later that I needed it.

I am wondering if I should pull the tranny and transfer case as a unit or can I split the transfer off first? I've never split one before, but I'm getting too old to be wrestling the pair if I don't have to, not to mention that I will have to split them eventually.

From everything I've read you can split them but expect to loose fluid out of both. Keep in mind the nv4500 fluid is very expensive and requires a certain type.

Like squareroot said AA bellhousing will make it easier along with going to a hydro clutch. You can also bolt a np208 or np205 to it so long as you have a 32 spline input shaft. For the np208 youd need to change it to a 32 spline shaft. As for length, I dont know where the two trans compare. But the nv4500 is about the same length as a 700r4 and would not require moving the transfer case but I'm going to guess the sm465 is shorter and will need the case moved back, this usually means different drivelines.
 

SquareRoot

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One of my 4500s came out of a 93 2500HD. It had a 241 case with a 32 spline input but you wouldn't be using that case anyway. My 85 that it's going into is a factory th400/208 setup with 32 splines as well. Either way, your t-case needs to be the round pattern. I don't know if there are short and long input shafts for the 208? My 205 had a long shaft that requires another....wait for it...AA adapter ring. It added 1 5/8" length to the setup. The 4500/205 setup is about 12 inches shorter overall than the 400/208 setup...a big difference. On my longbed, that means a 64" rear shaft or a two-piece setup.
These are just things to be aware of.

BTW, Summit sells the correct AC Delco fluid at about $18/quart. I recently bought a case (6) just to have it as it seems to be getting rare.

What I DON'T know is how guys are converting to hydraulic clutch setups in the pre-85 squares as there are no factory pedal assemblies for those?

I found it easier to split the trans from the t-case. They are very heavy especially with an iron 205! It's not difficult.
 

mcarlo86

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We are considering a NV4500 swap into our 90 V1500. I have a line on a good 4500 out of a 94 4X4 Chevy pickup. I also have a parts pickup '77 K20 with a 465 transmission in it. I'm wondering if the clutch pedals would work out of that pickup for the swap? I have seen that AA sells a NV4500 bellhousing for mechanical clutches so I wouldn't need the slave cylinder, master cylinder, etc. Has anyone had experience with one of those? I'm not positive on what t-case I have, but I think it is a 241? Would this t-case work with a NV4500? How about making it work with the factory cruise control?
Still wondering if anyone would know if the clutch pedals out of a 77 would work in my 90 burb on a 4500 swap using a mechanical clutch bellhousing from AA? Also wondering about cruise control since the 77 doesn’t have cruise? I thought I heard somewhere that there is a switch on the clutch pedal to disengage the cruise.
 

Josh Helm

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I have done the 3500 swap and love it ... minus needing to swap my ring gears now cause never use 5th under 80mph ... lol ...
 

SDJunkMan

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From everything I've read you can split them but expect to loose fluid out of both. Keep in mind the nv4500 fluid is very expensive and requires a certain type.

Like squareroot said AA bellhousing will make it easier along with going to a hydro clutch. You can also bolt a np208 or np205 to it so long as you have a 32 spline input shaft. For the np208 youd need to change it to a 32 spline shaft. As for length, I dont know where the two trans compare. But the nv4500 is about the same length as a 700r4 and would not require moving the transfer case but I'm going to guess the sm465 is shorter and will need the case moved back, this usually means different drivelines.

I have to split it sooner or later as I will not be using the transfer case that is on it, so losing fluid is not a problem, just a potential mess to deal with.

I will probably go with the AA bellhousing, although I saw a write-up that said that you could redrill a different bellhousing, but I can't remember where I saw it.

As for the driveshaft, I will have to have a new one made, as I am replacing a 465. Unfortunatly my 205 has the wrong input shaft , a 10 spline I think.
 

Dutch Rutter

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I do believe that you can replace the input shaft on a np205. I know it is doable on the np208 so I would expect it can be done. As for mechanical to hydro.... Since I'm preparing to do this one day I picked up a set of pedals for a hydro clutch truck on ebay. But that won't help much for the older trucks, I dont think.

here are a few links I saved a while ago for the clutch conversion

https://www.gmsquarebody.com/threads/upgrading-your-square-with-a-hydraulic-clutch.6589/

https://www.novak-adapt.com/catalog/clutch/kit-hcr3/kit-hcrc
 
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SquareRoot

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But th
I have to split it sooner or later as I will not be using the transfer case that is on it, so losing fluid is not a problem, just a potential mess to deal with.

I will probably go with the AA bellhousing, although I saw a write-up that said that you could redrill a different bellhousing, but I can't remember where I saw it.

As for the driveshaft, I will have to have a new one made, as I am replacing a 465. Unfortunatly my 205 has the wrong input shaft , a 10 spline I think.

I'm quite sure your 205 is the figure 8 pattern? You need the later 6 bolt round pattern 205. That's a much bigger issue than the input shaft. Or consider a round pattern 208.
 

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