Nice. Can someone list out the advantages/disadvantages of this truck mounted artillery w.r.t tracked self propelled guns? This system looks so sleek and fast in comparison to SPG's whose armor may slow them down.
Let's look at truck-mounted artillery in general (but with focus on the SPG role).
Firing to the rear is usually no issue unless the traverse is restricted.
Firing forward may cause trouble at low elevation because of muzzle blast (unlikely to still be an issue if you have gun overhang).
Firing sidewards is a big problem, and the recent 155 mm SPGs on trucks typically don't do it. The Italians used 65 mm mountain guns with soft recoil (the first such gun) on 4x4 trucks during WW2 and the recent
Hawkeye project uses the same concept - both times firing sideways is no issue.
There's another solution to the problem of firing sideways, though: Two or four stabilizers lowered to the ground.
All-round traverse can thus be had with moderately powerful guns on a truck, while powerful guns such as modern 155 mm howitzers tend to have a limited traverse similar to most towed guns.
These trucks typically carry some ammunition, but usually not as much as a towed artillery battery would be allocated per gun. So you either employ a second truck for ammunition and maybe additional personnel, or you end up being very mobile, but incapable of sustaining fires for long. This was certainly discouraging at a time when vehicle costs were a major concern and horse-drawn artillery a serious alternative (till well into WW2).
Concerning mobility; even some of the very first examples employed a 4x4 drive, and one of the Italian SPGs of WW2 wasn't only 4x4, but one of the very few dedicated vehicles ever specifically built for sand deserts. So some degree of off-road mobility can be achieved with truck-mounted artillery, and it's apparently usually satisfactory for the indirect fire role.
A major concern of the soft-skinned truck SPGs was certainly that the loss of the valuable motor vehicle was more likely if it was stuck with the gun than if it was able to withdraw away from the battery position. Then again, the ability to simply drive away once counterfire arrives was invaluable. It was the reason for the breakthrough of tracked SPGs in late WW2. So lightly armoured truck SPGs have this strength, but at the expense that the truck is additionally laden with about a ton of steel.
A truck is - even if lightly armoured - probably more lightweight than a tracked vehicle, but this is not necessarily so. Caesar weighs in at more than 17 tons with a 155 mm L/52 gun while the about 40 years older Mk F3 155 mm howitzer (shorter barrel) from France weighed about the same on a tracked chassis. A completely new lightweight 155 mm SPG on tracks and with similar traverse restrictions as CAESAR may easily be feasible at much less than 20 tons. Then again, light truck-based SPGs with 105 mm howitzers are down to much less than 10 tons nowadays.
*Here's some pros and cons of truck mounted artillery
Basically, tracked artillery is more mobile, tends to be better protected - though neither tracked or truck artillery are up to the standards needed to resist anything greater then small arms, and tracked artillery can better traverse aiming angles, while truck artillery has problems with firing in certain directions. Both require large supply trains though, and this is a major disadvantage.
