?Interesting about the switch in mid-late 01'*, Hope mine is later build like yours. I heard 1 thing about how to tell an early 01 to a late 01 visualy, I guess they changed the inlays on the trunk, some have the 00 type that I hear only has pontiac or bonneville embossed on the rear bumper. Forgot which one it had, They used the 00 rear bumber on 1/2 the 01 year than switched to having both pontiac and bonneville on the rear bumper. GM probably had extra 00 rear bumpers laying around and just used them up, doubt this switch came with the improved intake manifold, but maybe?

Can anybody confirm that there is a change? My 01 has both pontiac and bonneville one on each side of the rear bumper, do you 00 guys only have one side embossed?

my moms 2k has only Bonneville on it.

must be the extra HP & torque we get

My Bonneville was manufactured April 2001. It does have both" Bonneville" (left) and "Pontiac" (right) embossed on rear bumper. And I have no idea if it has an improved upper intake. I wouldn't know if there is any way to check, unless by VIN.

So my rear bumper theroy is correct than.
How do I find out when my 01 was made?

so whats wrong with the northstar?

I can name a few things, had one for three years and followed all the caddy/aurora boards for most of that time. They have common problems just like any other make and model. Btw caddy dealers aren't cheap either.
I wont name the common problems unless sombody cares,
I won't go there

Look at the data plate on the drivers door for month/year
of manufacture.