FIRING ORDER IS 1-8-4-3-6-5-7-2
18436572. it's the same as the old style gm v-8 engines. the cap has even #'s on driver's side and odd on the pass just like the motor. the cap is not in this order so be careful. the cap is marked.
1993 buick 3.8 firing order
Firing order: Industrial GM 3.0 inline 4: 1
the firing order on a GM HEI is 1-8-4-3-6-5-7-2
The firing order should be 1-3-4-2.
firing order is 1, 3, 4, 2
123456
CTS V6-3.2L VIN N (2003), firing order 1,2,3,4,5,6.
123456 is the firing order from the GM HAYNES REPAIR MANUEL
1342
165432
I have a 1998 Suburban with 60E transmission. It uses Dextron II. The 80E does as well. I used some stuff that supposed to work for Ford and GM cars. Seems to do ok.