Had some spare time so I decoded my RPO codes

[uhhhpooo]

Make sure the VIN on that SPID sticker matches the one on the cab. Those are easy enough to swap, and given the age of these rigs, it wouldn't surprise me if it was. Also, it wouldn't come a surprise if those codes had different definitions back in the day that these modern decoders aren't capturing.

the vin matches, and some of the codes match the truck, i need to have my vin ran to see about it instead of just the RPO codes

 

[Hipster]

yea it won’t have a 700r4, 700r4 was 88-90, then went to 4l60

4l60 still pretty much a 700r4, same service manual, 4l60e started in 93.

 

[uhhhpooo]

4l60 still pretty much a 700r4, same service manual, 4l60e started in 93.

yea

 

[uhhhpooo]

Make sure the VIN on that SPID sticker matches the one on the cab. Those are easy enough to swap, and given the age of these rigs, it wouldn't surprise me if it was. Also, it wouldn't come a surprise if those codes had different definitions back in the day that these modern decoders aren't capturing.

going say it is swapped, it was a frame off build in 91 and going say they put a 25 gallon tank

 

[DerekTheGreat]

Frame-off build in '91 eh? Yeah I'd be curious to see what that VIN search brings back, they could've swapped cabs or something.

 

[uhhhpooo]

Frame-off build in '91 eh? Yeah I'd be curious to see what that VIN search brings back, they could've swapped cabs or something.

yea i have to take pictures but the whole frame is red, and the cluster had 91 written on it and found receipts that said 91

 

[uhhhpooo]

Frame-off build in '91 eh? Yeah I'd be curious to see what that VIN search brings back, they could've swapped cabs or something.

you know anyone that does vin searches? or any free ones

 

[GoToGuy]

Found some interesting things about my truck, doesn’t have a 5.0 any more it has a 5.7, still has the 2.73 gears

There's one problem your overlooking. Yes you can decode the RPO spid tag. But that's not the end you also have use what year that option is built for.
GM recycles the codes. *** might be oil cooler HD. But it won't always be the same style or design. It may be unique to that year or a series of years. This is list is from the 88 service manual. These were the RPO for that year. I don't have an 89 , so is there that much difference between 88 and 89 ? This is the complete list, one page just one page. And " A52" is a bench seat. Using generic RPO listings can be misleading.

You must be registered for see images attach

 

[uhhhpooo]

There's one problem your overlooking. Yes you can decode the RPO spid tag. But that's not the end you also have use what year that option is built for.
GM recycles the codes. *** might be oil cooler HD. But it won't always be the same style or design. It may be unique to that year or a series of years. This is list is from the 88 service manual. These were the RPO for that year. I don't have an 89 , so is there that much difference between 88 and 89 ? This is the complete list, one page just one page. And " A52" is a bench seat. Using generic RPO listings can be misleading.

You must be registered for see images attach

yea, i mostly did it for rear gear and to conform it was the 700r4

 

[someotherguy]

I've said it many times that GM recycles some RPO codes. If we followed the generic lists blindly, I'd still be wondering where the 18 speed transmission went from my '93 3500, according to the widely-circulated "RPO Master List" from 2003. MT8 is not an 18 speed manual overdrive transmission. It's the 5 speed manual overdrive transmission (early NV4500.)

Following generic lists for RPO G80 may lead you to believe you have a positraction rear differential in your GMT400. No. You have a locker, the Eaton Gov-Lock. Thinking it's a posi would lead you to use the wrong lube additive and potentially cause issues with the Gov-Lock, which requires that you use no additive.

Richard