Dear Chris
The only Gribeauval guns in use in Russia were the 32x Gribeauval 4-pdrs as Regimental Artillery to the Young Guard.
No Gribeauval 8-pdrs were sent to Russia. The French had completely re-equipped with the AnXI [M1803] 6-pdrs and 12-pdrs. Some Gribeauval 12-pdrs were in use but not many. The Gribeauval 6.4in howitzer was obsolete. These were replaced by M1795 6.4in Long Porte howitzers with many of the 12-pdr batteries. Otherwise the AnXI 24-pdr howitzer [also given as 5.5in. 5.62in, 5.72in etc
] with a calibre of 150mm was in use.
The carriages for the AnXI system were modified in 1808 due to the French running out of money. Other excuses have been given but looking at the finances shows a little guilding. The woodwork was AnXI with Gribeauval 8-pdr wheels and metalwork.
Interesting the Kingdom of Italy seem to have used the AnXI system without modification. The few extent pieces seem to suggest this but more photographic evidence required.
The Saxons took M1766 4-pdr Schnellfeuergeschutz as battalion guns.
Guard, I-IV, VII, VIII, IX and XI Corps, I-III Cavalry Corps were completely armed with AnXI or derivative guns [Italian AnXI, Wurtemberg, Westphalian and Saxon] so had compatible ammunition & equipment. Regimental Artillery was Austrian 3-pdrs. The Polish Division in IX Corps had Prussian guns rebored in Dresden in Saxony.
Interestingly this left the Northern flank of V (Polish), VI (Bavarian) and X (Prussian) Corps with Prussian calibre guns.
This is explored in Dawson and Summerfield (2008) French Artillery to 1824, DP&G.
There were no recorded use of the 8-pdr as a field gun in the liberation of Germany as far as I am aware. The 4- and 8-pdr was still in declining use in the Peninsular. No 4- and 8-pdrs were used in the 100 days.
Stephen