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Hello from new member 77Jimmy

Hey Grim.
Last week, in my search for the VIN on the vehicle, I found a sticker on the drivers side door above where it latches and compared the VIN on that to the VIN on the build sheet/RPO list -- an exact match. There was no VIN on the dash. On my build sheet I have an RPO of 1M40 (says Tubro Hydramatic Tra and cuts off there, believe this is TH400). I don't have an 1MX1 RPO. Not sure if it makes a difference, but remember I have a GMC Jimmy not a Chevy K5. One code I've been wondering about is 1Z88, says GMC Conversion. I can't find anything on the build sheet that says camper or Casa Grande. I have also put a call in to Chevy and asked them to send me all the info they have on that VIN -- haven't heard back yet.
 
Welcome, we've got a good Atlanta group going. Hope to see you on the trails.
 
AZBLAZER!!!!!! What\'s the CasaGrande RPO?

See if Doug knows what that RPO is. I was looking over my wifes last night (it fell off and is now filed in the desk) and her truck is pretty loaded and I don't recall seeing that code before.
THe truck is too new to be anything like a "Feathers" (weird paint job deal). So that Modified means something. If it's not a Casa Grande missing the camper then that was a special order truck with some very odd options.
What other stuff does it list? The camper comes with some other HD stuff.
 
Re: AZBLAZER!!!!!! What\'s the CasaGrande RPO?

I can answer these questions, I think.

The RPO for the Chalet was 16T5; I *believe* the Casa Grande was the same, but I'm not sure.

The RPO mentioned for the GMC conversion is just that; they "convert" the Blazer into a Jimmy. My (1990) GMC Burb has that; it's a GMC, not a Chevy, so they give it an RPO for the GMC trim and insignia; make sense?

My 1974 Blazer came with 1M40 for its TH350 tranny. 1M40 is just for the auto tranny for your truck, not specifically for the TH400 (Chuck has a TH400 in his K20, so that's why he thought it was for the TH400.) TH400's didn't come in ANY half tons, stock, that I'm aware of; even the Chalets came with a TH350. They did often have a 400ci engine, but always had the TH350 AFAIK.

In other words, your '77 Jimmy is pure stock, just as it should be (and, with the exception of the GMC tags, just like my '74 Blazer. 350/350/203.)

-- A
 
Re: AZBLAZER!!!!!! What\'s the CasaGrande RPO?

dremu,
Thanks for the info. The pieces of the puzzle are coming together. Man, that 1M40 RPO is confusing as heck -- that's the first that I've heard of or read on this site (or other numerous sites) that the 1M40 doesn't mean you actually have a th400. I'm not saying I doubt you but man, thanks weird. Guess it's a GM RPO quirk.
 
Re: AZBLAZER!!!!!! What\'s the CasaGrande RPO?

Re the 1M40, it stumped me too -- but my '74 has a TH350, always has AFAIK, and I've never heard of Blazers/Jimmies having TH400's. Occasionally you might find a 1/2 ton pickup with one, which is allegedly factory, but as you say ... the General is known to break even its own rules every now and again ;-)
 
Re: AZBLAZER!!!!!! What\'s the CasaGrande RPO?

I'll have to look at the 75 Jimmy when I get home and see what it says. The 79 blaser lists "1MX1 Three speed automatic.
 
Re: AZBLAZER!!!!!! What\'s the CasaGrande RPO?

Grim/dremu,
Just to close this one off, I looked over the build sheet one more time just to make sure there wasn't anything out of the ordinary. Unfortunately, it's ordinary...
1HE3 -- 3.07 gears
/forums/images/icons/frown.gif
 
Re: AZBLAZER!!!!!! What\'s the CasaGrande RPO?

Don't feel bad about the gears...probably 90% of 70's K5's had 3.07/3.08's.

Rene
 
Re: AZBLAZER!!!!!! What\'s the CasaGrande RPO?

I think both Depdog and Keith have a set of built axles for sale. Bother should be 12 rears with 4.56 and Detorits. Keiths front will be a 10 bolt and Deps will be a D44. I think Deps set had a Lockright in the front. Not sure what they are asking and the axles are still under the trucks for another week or so.
 
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