Grease/brake fluid on the rotors or pads.

I had a similiar  problem with when braking in a '95 Dodge Intrepid. At
it's annual inspection it was reported that there was a brake imbalance
on the front brakes. It just about got through the inspection because
of this. On checking the pads, the LH brake pads were much more worn
that the RH side. So I invested in new brake calipers and new pads.

So I was a bit disappointed when the stuttering problem continued. I
took the car to a local garage and they ran a few tests. They were at a
loss to diagnose the problem. Although the mechanic observed that the
LH outboard pad moved slightly on the caliper when the brakes were
applied.

Anyway, to cut a long story short, the problem slowly and gradually
disappeared as the pads and the calipers bedded in together. Much
relief all round because the next step would have been to replace the
front discs. So I hope that this might you some ideas...

Alan

Cheltenham
England