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Looking for information on 1976 chevy BONANZA which has dual exhaust and a full time 4wd two speed transfer case,only high and low.This was an Arizona truck whose title list the original price of vehicle and states cost at $6875.00.Is anybody knowledgeable on mid 70s pickups that can help me find information. My deceased brother told me there was two of these truck built and this one is the only one left.
Steve

I think that the Bonanza is a trim package. I had a 1976 Surburban with fulltime 4 wheel drive, dual exhaust, A/C and transmission and engine oil coolers and the shifting lever for low and high. It had a 400 cubic SBC and turbo hydramatic, there were many Chevrolet trucks made like it, pickups, panel wagons and Surburbans, all with the same drivelines, various engines and manual and automatic transmissions (350s 400s and 454s) and diesel. I got a shop manual from Chevrolet, also there were other aftermarket shop and repair manuals made for it. Check with Faxon literature on eBay. I rebuilt my engine, transmission and transfer case and the double U joint back in 1982 after the truck had 200k miles pulling trailers. I traded it off in 1995 for a 2 wheel drive 1500 extended cab Silverado.
By the way what is a copo truck? a Cab Over Pickup, or what?

Do a search on Google and you will find that there are a fair number of 1976 Chevrolet Bonanza pickups listed there.

Not sure what you're asking here. But, "copo" is the acronym (?) for Central Office Production Order (COPO). Dealers (like Yenko in PA) used this procedure to get "special order" cars. Like Camaro's with bigger big blocks in the 67-69 years. Like 427's instead of 396's. Those Camaro's were (likely) also equipped with bigger 'high performance' suspension, "stripped down" interiors, limited "comfort" options, 140 mph speedometers, gauge packages, tachs, etc. etc. etc.

I'd say this COPO deal was essentially a back-door around Chevrolet's performance limits.

I'm not totally up to snuff on this history stuff, but I figure it was probably a 'dealer-only' type situation early on. And eventually became something any old Joe (like me or X?X?X) could do.....

Bill.

...Yeah, but in this thread, Bill I think, maybe copo isn't quite legit for a common 4X4 pickup with a trim package. But again, we didn't get to see a picture of his super rare truck.... I think that there is something blowing smoke besides the dual pipes on the truck.

The sticker price for the 76 surburban was a shade over $10,000 with front & rear A/C heavy duty suspension and a trailering package that made it a 5/8 ton and kept it exempt from having the anti-pollution air pump and cat converters.

not looking at Bonanza package Looking at transfercase with two positions . Standard has 4 positions high lock and hign, I asked if the np203 can be coverted to just two positions from tansfercase guys and did not really get an answear?

was dual exhaut available in 1976 , if I remember right corvetts had fake dual in 76. were dual exhaust available on trucks? This trucks transfercase only has two positions low and high, the np203 has 4 positions high lock with high and low lock with low.

bit more to it than package,how common was dual exhuast in 1976 besides that the transfer case has only two positions low and high not low lock and low-high lock and high. My brother tried to unlock hubs and burned up trans going around block. Brought rebuild kit for np203 transfer case and none of the parts would work . H had to match bearings at bearing shop. I asked transfer case guys if np203 can be coverted to just two positions with no answear. Some where in this website there is a price range for pickups at low to high $3000 is this not accurate. As far as photos goes it is just a shortbed Santa Fe tan and white 4X4 pu with ralleys

What engine and transmission does your truck have in it? Have you found parts for the transfer case yet? Is the front tire tread with wider in front than in back? My Surburban was. The Bonanzas I saw were all short narrow bed jobs, if I remember right.

I also have a 1988 GMC trailering special 2 wheel drive extended cab 2500 with a 350 and single exhaust with a 5 speed manual OD transmission.

I replaced the mufflers and tail pipes several times on the Surburban and the exhaust pipes and exhaust manifold gaskets and sparkplugs several times. Climbing a steep grade from Dalhart Texas up to Santa Fe in 100 degree weather would heat up ehe engine compartment so hot It was like an oven when you opened the hood. It had engine oil and transmission oil coolers and an A/C condenser in front of the radiator and the fan would sound like an airplane most of the time. I abandoned the fan clutch and installed a aftermarket flex blade fan. That worked better, but was always noisy. I often wish I had that old Surb back again.
I figured that dual exhausts were common in the 4x4 with full time 4 wheel drive that were rated as 5/8 ton because the 1/2 ton trucks fell within the emmissions control which applyed to 1/2 tons and lower, which got the cat convertor and air pumps. I had several 5/8 tons to pick from at the dealer. I went with the blue and white Surburban with the trailering special package. 1976 was right in the middle of the pickup and travel trailer craze with $.40 gas, I thought it awful when I had to give $.60 for gas in Colorado on a vacation. It may have been premimum fuel. . My brother had a 76 4x2 Surburban with a 454 engine and HT400, he drove it over 250K miles hauling pottery from Mexico to DFW area. One thing that was pecular to the 76. It had was no rain gutters above the doors, I bought the new ones that came out later, they were plastic and were attached with pop rivits and GE clear RTV. The 400 SB started acting strange at 80K miles. It started using a Qt. of oil every 500 miles, would smoke out the exhausts when you let off the gas, and when it got a Qt. low on oil the valve lifters would start th chatter. I tried to find a 400 crate engine but none were available, so I overhauled it in my shop/garage. Also had high performance clutches put in the 400 HT. I found that the oil pickup to the oil pump had come loose and was in the bottom of the pan, the oil pump wasn't getting enough oil when it got a QT. low. I replaced pistons, rod inserts, mains and camshaft and cam bearings along with valves and lifters, also added aftermarket oil seals, which is what caused the oil consumption. It was a good engine from then till I traded it in in 1995 with over 140K on the odometer. It was our second car and used almost exclusive to pull trailers, hauling cars, pickups and camping trailers, often grossing over 10,000 Lbs. that was right at the limit, maybe a tad over. I hauled F-350 pickups several times. The transmission was needing a new torque convertor when It was traded it off. Often when first started up after being parked for several weeks it would be ok for 500 yards, then when I turned a corner it would lose prime in the converter and need to be reved up, then go ok for all day. I also rebuilt the u joints front and rear several times.

Comforting info coming from a guy asking what COPO is?

Everything in truck works but all this happened with my brother in the mid 90s so I forgot most things he told me about truck. I do remember sending him to brown bearing to match bearings, They put it back toghther with what they could get and he was stuck with rebuild kit and hubs. When he passed away I was speaking to his best friend in AZ and he claims my brother showed him online where this was one of kind truck, not sure if a package issue or what. The only way to find out is to take apart transfer case which is not planned. The trasfer case guys never gave me an answear about this case ,do you know if np203 can run in just low and high position.

this is a 1/2 ton truck with 350 c.i.d. turbo 350 trans and full time 4wd 2 positions

I kind of knew about what a COPO was,.... but not a copo, A COPO is a CO-OP thing: Constipated Old Plow Operator. When I wanted to special order a Chevrolet I just went up to the Chevrolet dealer and told the owner "Hey Chas, I need to order another one of them Chevrolet pickups, you know the Heavy Duty tricked out ones like we use out at our place!" and in a couple of days or weeks he would call and say" Hey Mack, We got your pickup in today!" That is how we do it out here in the boonies.....

Here is "Old Blue" he's been around for a while



...and "Old Silver" & (Klinkerbelle's ride) we replaced him a couple of years ago with one just like him.....

A COPO could be anything that normally wasn't installed on the production line. A example is prior to 1966 Chevrolet base trucks didn't have a RH inside sunvisor these could be handled on a COPO basis. On the far side of the COPO price list a 425HP 427 engine could be installed in 1969 Camaros and Chevelles

Yeah,... Special paint, heavy duty tires, PTO on left side, Yadda, Yadda, Yadda.......

dual or single exhaust in 76 had to do with GVW, gross vehicle weight. a C10 would have a catalytic converter, required unleaded fuel and dual exhaust was not available. a K10, because of the heavier weight, did not have a converter so regular fuel was used and duals were available from the factory. By 85 you had to go to a K20 to avoid a catalytic converter.

I ordered a 76 C10 and had the converter removed and duals installed at a muffler shop. at that time muffler shops had stacks of converters laying around. In January of 77 I ordered a K10 after a monster snow storm. I had the copo part time 4WD option number but the local dealer didn't have the juice to push it thru. I ordered it with duals. sometime between 77 and 81 GM dumped the full time set up and went back to part time with auto locking hubs.

there should be a round tag on the transfer case denoting the series of case. retro kits were avaiable to convert full time to part time cases. some worked well, some didn't.

the full time cases had 4H Lock, 4H, Neutral, 4L, 4L Lock. part time systems should have 2H, 4H, Neutral, 4L.

This transfer case only has two positions 4low & 4high too much crud on transfercase to look for tag, where would it be located. The case looks like np203. There are some heavy duty battery cables going to the back of the truck that are not connected,looks like factory. Also looks like something on the back of the frame was cutoff.

Thanks for the reply , I was a motor head from the seventies and know what COPO is . I heard there were some trucks made it the seventies but do not know anything about them. I am not really into trucks,I just have it for sentimental value. I really want a 67-73 original camaro with manual or corvette. Anybody have anything to trade?

Steve

I wrote a bunch of transfer case rebuilders without any answears. If I remember right my brother told me that this was a prototype transfer case.This was back in 1995 when he told me all these things, the only thing I a sure of is that rebuild parts were not available and I suggested Brown bearing to match any bearings for replacement. Is this thing a real prototype, do we really have a one off vehicle that has surfaced. I call the truck Bobbie because three people have died in this truck. The original owner was a retired GM excutive whom passed away of a heart attack in the drivers seat, the next owner hot rodded it and had a blower sticking through the hood and tried to cross a flooded sand wash in AZ when the blower sucked water and stalled in the river and he drowned in the drivers seat. When my brother got it I asked him if he was superstious and he did not like it but was a good price, he put it back to stock and claimed it was all original and all this one of a kind prototype thing but ended up getting murderd in the drivers seat.He had the transfer case apart and was in the car business all his life as a mechanic so he would know. I have had this thing for 12 years now with a couple of strange circumstances but still here. The only reason I have it is because I never seen him get so crazy about a truck and he had some nice stuff 442,SS among other things and nothing seem to excite him this much. I am not scared of this thing and because of financial reasons I want to sell it and want to know whats its worth. Do we really have a one off protoype?