Maybe post up a picture. I checked the lifters in my garage out of a 2006 6L and they dont have any numbers on them.

I wouldnt worry about it as long as you know they are low mileage.

 

I posted pictures of the early open style and the closed style. The closed style is the LS7 style lifter.
We can't see what the stuff you bought looks like so how can we correctly answer your question???

 

Ok lifters are at my work, it will be monday before I can post a picture. Appreciate the help!

 

You guys stay up too late hah. Anyways what 1fastbrick said^

 

Posting this pic for the OP...these are the lifters that he is trying to find out if they are ls7's or not.

 

They look like LS7 lifters to me. Either way it doesn't really matter what they are as long as they are in good shape. I have seen ls7 lifters fail just as often as the regular ls1 lifters. The ls7 are just the replacement for the ls1 style lifters so that's why everyone gets them. I don't think there is any advantage to them other than being newer.

 

Actually there is a slight difference betwen the original open design and the later closed design. But it's so minor you wouldn't notice unless you measure it. It was redesigned to make it more reliable part.

Looks like you have the more desirable part. You should be fine. The same part number services several engines.

 

i just went out and opened up a brand new box of ls7 lifters and the OP's look exactly like what i have. i wouldnt worry one bit, just go install them. for reference, the part# on my box is 17122490...

 

#17122490 -GM LS7 Roller lifter This Number is for a single Lifter, They are packaged in sets of 8
#12499225 -GM LS7 Lifter Package of 16 Rated up to 7000 RPM This is the number for a package of 16

 

correct, i shoulda been more specific. I opened up a box for a single lifter within the set.