I know this is an old thread, but to the person having issues with their kid's Slash's Titan 12T motor -- those motors are OFTEN reported to be duds and bad in quality on several RC forums. I'd stop paying $15 for new ones and look up an inexpensive Castle or Hobbypartz (EZ or XE-run model) Short Course truck brushless motor combo. They're getting cheaper and cheaper, right now you would be hard pressed to find a better upgrade than a $100-$140 brushless motor. Infinitely better and more importantly, consistent performance, and runtimes! I've been running a $160 Castle Neu 1518 1800kv brushless motor in my 10 lbs Traxxas Summit crawler/truck paired with a cheap $90 "XE-Run" 80 amp brushless ESC. My Slash runs a 4-pole Medusa 3000 Kv (rare finds!) motor paired with a <$50 60A chinese ESC. Both have run well for over a year and I have never been happier.
The 1518 motor is 4 pole and almost impossible to stall (I actually bought it on clearance for $65 from Castle!) in my Summit, although I believe the truck will grind its gears before it stalls with the stock 700 sized brushed drill motor! LOL. Granted I'm not talking about hardcore crawlers here.
Anyway, just thought I'd register to offer some insight. I'm actually addicted to R/C and cars. Right now I'm reading up on Land Cruisers (FJ60-80) to see if I want to delve more into hands on tooling/maintenance etc., now that they can be found for < $3-4 G's.