Did 1970-1972 Chevy 402 Trucks have the VIN stamped in the block from factory?

[HeavyHauler]

I am trying to figure out if my friends 1971 Chevy truck has the original engine that it came with from the factory. For 1970-1972 Chevy truck 402 big blocks did GM stamp the VIN on the block?

If GM didnt stamp the VIN on the block for 1970-1972 trucks then how do you really know that you have the exact engine that it came with from the factory unless you are the original owner?

Another weird thing is that the truck has 400 badges on the fender but has 396 for the engine size on the SPID sticker. He claims it is original but it seems like it probably came with a small block 400.

[harpo231]

The only VIN numbers will be on the cab, frame, glove box door and build sheet.

[Steeveedee]

The stamped characters will only give you the application. That might span a couple of years.

[leddzepp]

Originally Posted by HeavyHauler

I am trying to figure out if my friends 1971 Chevy truck has the original engine that it came with from the factory. For 1970-1972 Chevy truck 402 big blocks did GM stamp the VIN on the block?

If GM didnt stamp the VIN on the block for 1970-1972 trucks then how do you really know that you have the exact engine that it came with from the factory unless you are the original owner?

Another weird thing is that the truck has 400 badges on the fender but has 396 for the engine size on the SPID sticker. He claims it is original but it seems like it probably came with a small block 400.

You don’t know...it’s just a guess. 400 badges indicate either a 396 or a 402, they do not designate a small block 400.

[68Gold/white]

68 and 69 had 396's. 70-72 had 402's.
No fender tags for the 396's, some 70-72's had "400" emblems...

That's what I know....

[HeavyHauler]

So anybody could have just tossed in any big block 402 engine and call it the original engine. I guess there is really no way of telling if its the original engine or not then.

Thanks guys!

[bluek5]

Originally Posted by 68Gold/white

68 and 69 had 396's. 70-72 had 402's.
No fender tags for the 396's, some 70-72's had "400" emblems...

That's what I know....

Not sure about the no fende tags for the 396’s.

[uncle]

396 fender badge in 1969 only.

[harpo231]

Originally Posted by HeavyHauler

So anybody could have just tossed in any big block 402 engine and call it the original engine. I guess there is really no way of telling if its the original engine or not then.

Thanks guys!

bingo !

[KevDiesel]

The suffix code stamped into the block deck identify the original type of vehicle the engine came from... Decode the block and you can tell if the engine matches your vehicle. Use the below website as a reference. There are books and many other websites available to research.

http://www.1968ss.com/bbcsuffix.asp

[uncle]

Pretty sure most truck 402’s prefix started with T and cars with C. One easy way to tell. That would only be good for 70-72.

[jocko]

Most of your questions are answered I believe.
Bottom line - a 71 big block truck would have a 400 badge under the marker light and 396 or 402 on the SPID. If 396 on the SPID, it’s probably early in the production year (but still likely a 402 under the hood). Look at the engine pad stamp and run the numbers to determine if it COULD be original to the truck - COULD does not mean IS. Anything beyond stating it is possibly the original engine is speculation unless it’s the original owner stating it. And I don’t often believe them either. Once you confirm it’s possible, you kinda have to just look at it and assess if it’s ever been removed to build confidence in an “it might be original” statement. Although anything could be swapped on or off, you can also date the carb and other parts to add to or detract from confidence level.

[HeavyHauler]

Originally Posted by KevDiesel

The suffix code stamped into the block deck identify the original type of vehicle the engine came from... Decode the block and you can tell if the engine matches your vehicle. Use the below website as a reference. There are books and many other websites available to research.

http://www.1968ss.com/bbcsuffix.asp

That would not prove anything except date code of the block itself and type of vehicle but nothing specific. Might as well get any bigblock at that point because it wouldnt be the original engine anyways. Thanks for the info though.

[HeavyHauler]

Originally Posted by jocko

Most of your questions are answered I believe.
Bottom line - a 71 big block truck would have a 400 badge under the marker light and 396 or 402 on the SPID. If 396 on the SPID, it’s probably early in the production year (but still likely a 402 under the hood). Look at the engine pad stamp and run the numbers to determine if it COULD be original to the truck - COULD does not mean IS. Anything beyond stating it is possibly the original engine is speculation unless it’s the original owner stating it. And I don’t often believe them either. Once you confirm it’s possible, you kinda have to just look at it and assess if it’s ever been removed to build confidence in an “it might be original” statement. Although anything could be swapped on or off, you can also date the carb and other parts to add to or detract from confidence level.

Yep I think you have summed it up very nicely. Thanks!

[crakarjax]

How rare are 402s anyway? The block in my chevelle is actually a '72 truck 402 block and I'm wondering if I should move it to my truck when LS swapping...

[HeavyHauler]

I have heard and read in numerous places that there are more 1969 Camaro Z28s in the United States now than GM ever produced. I see how that can happen now.

[Steeveedee]

Originally Posted by HeavyHauler

I have heard and read in numerous places that there are more 1969 Camaro Z28s in the United States now than GM ever produced. I see how that can happen now.

Them and SS Chevelles. I worked for a couple of Chevrolet dealers off and on from '70 to '72. I saw maybe 6 SS Chevelles out of the 700 vehicles we sold in '70, for example.

[KevDiesel]

Originally Posted by HeavyHauler

That would not prove anything except date code of the block itself and type of vehicle but nothing specific. Might as well get any bigblock at that point because it wouldnt be the original engine anyways. Thanks for the info though.

"Numbers matching" and "original engine" are obviously different... and it all depends on the owner or a potential buyer.

In my case, I have a 1970 Suburban C20 with a block stamped T0427TBG. My SPID states it came with a 400 cubic inch engine. When I decode the block, it tells me the block was used one year only (1970) and was put into 1970 Trucks/Suburbans, was rated at 310HP, and was used in all 10, 20, or 30 series chassis. The casting codes on my heads are correct for my year, the casting code on my intake is correct for my year, the casting code and date code on my carb is correct for my year. After all my research, I am comfortable stating I have a "Numbers Matching" vehicle. As far as it being the exact original engine, only the original owner would know...

[HeavyHauler]

Originally Posted by KevDiesel

"Numbers matching" and "original engine" are obviously different... and it all depends on the owner or a potential buyer.

In my case, I have a 1970 Suburban C20 with a block stamped T0427TBG. My SPID states it came with a 400 cubic inch engine. When I decode the block, it tells me the block was used one year only (1970) and was put into 1970 Trucks/Suburbans, was rated at 310HP, and was used in all 10, 20, or 30 series chassis. The casting codes on my heads are correct for my year, the casting code on my intake is correct for my year, the casting code and date code on my carb is correct for my year. After all my research, I am comfortable stating I have a "Numbers Matching" vehicle. As far as it being the exact original engine, only the original owner would know...

That is true and I agree. It sounds like you have done your homework on your engine and that is something I will also have to do in order to determine the level of "numbers matching" for the engine that I was talking about.

[67RSS]

Originally Posted by KevDiesel

"Numbers matching" and "original engine" are obviously different... and it all depends on the owner or a potential buyer.

In my case, I have a 1970 Suburban C20 with a block stamped T0427TBG. My SPID states it came with a 400 cubic inch engine. When I decode the block, it tells me the block was used one year only (1970) and was put into 1970 Trucks/Suburbans, was rated at 310HP, and was used in all 10, 20, or 30 series chassis. The casting codes on my heads are correct for my year, the casting code on my intake is correct for my year, the casting code and date code on my carb is correct for my year. After all my research, I am comfortable stating I have a "Numbers Matching" vehicle. As far as it being the exact original engine, only the original owner would know...

Hey Kev/anyone
Where is the stamp?- I have looked at my 402 pad and oil filter area and neither have any indication- I assumed Big Blocks were not stamped on deck pad..(and stamped in block) either that or mine was decked in past..
thanks Lane

[KevDiesel]

Originally Posted by 67RSS

Hey Kev/anyone
Where is the stamp?- I have looked at my 402 pad and oil filter area and neither have any indication- I assumed Big Blocks were not stamped on deck pad..(and stamped in block) either that or mine was decked in past..
thanks Lane

The stamp is on the passenger side front of the block on the deck surface. It could have very well been decked off. FYI, I am located in Livermore as well.

[67RSS]

Ah thanks Kev...I know mine was rebuilt..decked I guess!

Thought the big blocks were different from my Camaro experience..

I think I saw yer Burb in a parking lot in town...that thing is huge- seats looked nice!

I have 72 Custom Camper highlander...red & silver two tone- bought from a friend in Walnut Creek in '93. Was orange (med red) & white..never understood that color designation.

Mostly use it to go to Delta to tow my boat...

Lane