I'd strongly suggest reading the care instructions and if they are gone, ask Timberland. Random chemicals, harsh cleaners, strong detergent or even hot water can permanently ruin some waterproofing fabrics.
Find out what you can or cannot safely use, then try to figure out what the stink is. Urine? Mold and mildew? Decaying plastics? Different approach to each. And Timberland may have something to say, in terms of warranty.
If the material can take it, and the stink is from something that got into the clothes? I'd suggest a good soak in a front-loading washing machine, with a premium detergent and Oxy-Clean (which is a non-chlorine bleach that works on many things). If the stink is simply from diesel fuel, just put the clothes on a clothesline out in full sunlight for a couple of weeks after a good washing. Very little gets out diesel stink if it gets into the wrong kind of materials.