The Cascavel is protected by an unusual dual-hardness aromr configuration. It consists of an outer layer of hard steel and an inner layer of roll-bonded, heat treated soft steel. I assume this is to reduce spalling. Even if a large round bounces off, or even in the case of a penetration, the softer steel will spall less. Fragments from the hard outer layer caused by the penetration would be held by the softer inner layer, which would tend to bend rather than break-off. So more often, you'd get a jagged hole, but all the armor still attatched to the surrounding armor. If the armor were all hard, you'd get a hole, and alot of fragments and splinters from the armor flying around inside as well as the projectile that did the penetration. This is just my assumption, but it's one of the reasons aluminum is used under steel in many vehicles. I'd say in this case, the dual-hardness allows the use of cheaper steel, and probably gives better protection than alloy/steel combinations.
The suspension is basically what ENGESA used on their 6x6 tactical trucks, so it has good cross-country perfromance, and can move pretty quick on a road too. It uses a Detroit Diesel 6 cyl, 212HP powerpack to move the Cascavel up to 62MPH (100KPH), and economical enough to drive 550 miles (880KM), it does pretty good on the roads and hills of South America overall. It is not amphibious, but can ford 1 meter without preperation. It's supposedly simple and fairly easy to work on, but not really built for higher levels of maintenance out in the field.
It's armed with a Brazillian made version of the 90mm Cockerill gun and is equipped with a laser rangefinder, and the usual fire control stuff. The usual 7.62/.50 Brownings and smoke launchers is also fitted.
There's no NBC system, or air conditioning, and some have Benz diesel engines. The Urutu is basically an APC version of the armored car, and shares most components. It can be equipped with Milan AT missles, and the usual other stuff just about anyone can tack onto any APC.
They're very successful designs that have done quite well for Brazil's arms industry.