I am getting ready to put new undercarriage on two D4E SA Ag Cats.Cats pushin for me to try extreme service track pads an additional $700.00 per set.
90% our work is steep hillside work discing.Any thoughts on additional cost between standard pads and extreme service pads.

The only time you need extreme service shoes is when you're ..

A. Working in rock ..
B. Working in material or conditions that load up the outside edges of the shoes ..
C. Working in very abrasive material ..
D. There is a lot of track slippage due to constant full power application at low speeds ..

I would not consider 90% ag discing work, extreme service, by any stretch of the imagination.
The extreme service shoes are heavier construction overall .. slightly increased hardness .. with a thicker plate section, more robust heel .. and a thicker and higher grouser (about 30% thicker overall).
They pay off in rock, highly abrasive, and high slippage conditions .. but I've never seen anyone use them on ag work .. which is almost always regarded as light-to-medium duty service.

The only factor in their favor as far as you're concerned, is that with the additional weight of the shoes, the tractor will end up with a lowered C-of-G, which may be of benefit, when you get on sideslopes, that make you fall out of the seat ..

The downsides to extreme service shoes, are that ..

A. They make penetration more difficult in tight soils ..
B. They reduce tractor manuveurability due to higher grousers ..

Here is a useful CTS chart, giving the +'s and -'s for each direction you move .. in relation to shoe width, thickness (of grouser and plate section), hardness, the height and the number of grousers ..

Thanks Oz Dozer for the input.I have decided to go with one e.s. pad set and one standard to see which one works best.This season should be a good test as we have gotten a lot of rain this year.We are using these D4s for cutting fire breaks.We dont have the luxury of discing farm land(at least there you can see the ground).Itought to be to be interesting to see how much better the e.s. pads are if any while side hill discing as the soil is extremely loose in most areas and the vegatation this year will be higher than normal.Thanks John