i have a 1985 K10 chevy and i am currently performing the either stupid or bold swap (i prefer bold). after research after research after research, i have finally figured most of it out.

i have a 350/700r4/np208 and want to convert it to a 292 i6/sm465/np208. so far i understand that i will have to get a new input shaft (32-spline) for the np208 and "short" np208 to sm465 adapter. i think i have the steering column figured out and i dont think i have to do anything to the crossmember.

my problem is the clutch linkage: i know absolutely nothing about it. what is a z-bar, mechanical vs. hydraulic - what is the difference????

please help and if have anything wrong, please let me know. thanks for the help!!  

oh and so you have a better understanding as to why i am doing this: i bought the truck about a month ago for a project truck, the frame is PERFECT (straight as an arrow) and the body has ZERO rust. the 350 is some really crappy aftermarket (orange block) engine and the 700r4 is on its last leg. i figure if i am going to do the swap, now is the time  

Nothing wrong with a 292. It was a great engine in its day especially in its non smog form. Nobody talks about them much anymore. That year truck offer a 250 six and 292 is same basic block except taller so look for 250 clutch linkage parts. Clutch should have a pivot bar that goes between frame and a screw in stud in block and that connects to linkage on pedal and also to throw out bearing fork. There is a heavy counter spring that goes under dash that assists with pedal effort. GM 6's and V8 have same bolt pattern on bellhousing. It is a shame that you are dumping the 700R4 though because with a decent set of gears in axles and the 700R4's OD you could have a truck that is a stump puller and cruises nicely too. For what it is worth, most 700R4 fail because users put big tires on them without regearing axles and burn trannies up riding stall in OD a lot. 700R4's are not to forgiving of this practice.  

Thanks SnoMan!
I dont have a problem with the performance of the 700r4. I just want a transmission that I can work on myself and the sm465 looks like a good candidate (if there is a better, more pratical transmission please let me know)

i want to do a 292 i6 because it will give me better gas mileage and a whole lot of torque. im not a big tire nor rock crawler guy, i just want a small tank. im only gonna put a 2.5in lift on it with 33in tires.

and to help me out a little with the clutch linkage, am i looking for hydraulic parts or mechanical parts? also, i just bought a pedal cluster off of ebay the other day, i hope i bought the right one.  

Clutch is mechanical on that body style. I might suggest that if you really want to "play" with the 292 and try to squeak out best MPG, look for a N4500 to adapt in.You will take a hit on that big 6's MPG potential without OD. (old pre-smog 292's peaked their torque below 2000 RPM and would pull strongly from about 600 RPM or so) GM started offering them 92 and had to style bell housing for them (92 to 96 and 97 to 07 when they dropped it) Those are hydraulic. If you go this route, look for a 92 to 94 GM 4500 as it had a deeper granny than later ones (about same as 465) All 4500 have OD and they shift MUCH better than 465's as they went to pains to refine shift quality. A would rate a 4500 slightly about a 465 is strength too. (not that a 465 is weak by any means) Again if you go 4500 route, you need to match tranny to bellhousing as there was two of them. THe engine side is fine as either one will bolt right up to 292.

BTW, I had a 66 chevy 3/4 ton over 33 years ago (it ages me doesn't it) with a 250 six and a 4 speed and that was a great truck and ran well. I towed a car on a trailer from Ohio to NC once and it pulled it fine even on highway. That would have been a neat truck with OD.  

i am pretty good when it comes to mechanics and like i said, would love to do everything myself. is the 4500 more difficult to rebuild? and if so, how much harder? how much more expensive are they?

ive read about the differences between them and the extra gear would be very nice!

when i was in high school i had a 1985 4x4 gmc 3/4ton SWB (pretty rare). i think it was called it a heavy-half. i loved that truck

thanks for the help SnoMan!  

If you go 4500 route you want to stay away for Dodge versions. Dodge used it to and up until 99 or so they had issues with 5th gear because Dodge did fifth gear retainer and collar different than GM (cheaper). If you find a 4500 it will likely not need a rebuild as they are quite sturdy and the oldest is only about 15 years old. Later GM versions were tweaked a little more on shift quality but the have a taller granny and reverse too. I am not knocking a 465 as I drove a few of them and one for 10 years over 20 years ago. They never were great on shift quality and smoothness and 4500 is far more refined in that regard. 4500's were mated to NV241 Tcases in 92 on GM trucks but this Tcase has drop on wrong side for you but GM also used a 241 on 88 through 91 full sized blazers and burbs which were still old body style with drop on passenger side for front axle. This would likely ease the tranny/Tcase issue with a 4500.  

so... if i can find a good nv4500, will it bolt directly onto my np208 without an adapter? would there be any crossmember changes? and would finding the correct bellhousing be my only problem???

thanks again for the help  

Not sure on a 208 you have. Your problem there is that they usually use different splines on automatic and manual tranny Tcases back then. I suggested finding a 241 out of a 88 to 91 as it should be easier to mate with a 4500. Worst case senario, you can always get a adapter to put between 208 and 4500. On mount it should not be a big problem  

ok, what if i changed the np208's input to a 32-spline, whould it bolt on then?

also, i found a guy ***
"GM NV4500:
Pulled out of wrecked 1997 3/4 ton chevy pickup with 124k miles. Flywheel and gear shift included.
Will trade for 700r4"

is that a good deal??? (given the trans is for 4wd)  

Okay, I did some double checking to be reasonably sure here. Yes it is a good deal get bellhousing if you can because yours will not work. If you cannot get it get a 95 to 2000 bellhousing from a 350 or 454. (they change style in 95) On splines, my records show that GM NV4500 has 32 spline output (Dodges could have 23 or 29 spline)and will bolt to GM Tcases after around 85 so since yours is 85 you need to double check tranny to tcase bolt pattern. Youy will likely have to do a little fabbing on cross member but it should not be a big deal.  

SnoMan!

ive done a lot of thinking, im gonna go with the muncie. i would love to have the nv4500, but its too expensive and i dont want to go anywhere near fabrication.

also, my budget (which isnt much) is quickly dwinling. i found rust on a part of my floorboard (pen size HOLE), and when i went to put new bearings in my rear axle, i found an almost destroyed differential.    

ok... ive called all of the salvage yards and all of the transmission shops with no luck. everywhere i call they act as though finding a sm465 is like finding a needle in a hay stack.

please help, is there an other places i can be looking???  

Have you tried "www.car-part.com"?  

greatest website ever! thanks SnoMan