It's not just Chevy or Cadillac. My wife's daily driver is a '98 Olds Intrigue. I couldn't believe it the first time I went to replace spark plugs and couldn't get a wrench setup on the back 3 plugs of the transverse mounted V6. I finally gave up and took it to a local shop to replace those plugs. The mechanic told me you have to disconnect the motor mounts and rock the engine forward in order to get adequate access to the back plugs.
That's insane!
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