Where can I find a higher melting temp solder lead like the one soldered on the ESC's output and input wires?

Huh.. For what? If your melting the solder I would think you have other problems.

I ve been using Much More racing solder lead with 30watt solder and it melts with no problem. Now I wanted to replace the 12awg wires that is soldered to my esc....the problem is my 30w solder cant even melt the factory solder....so i was thinking if i get a better solder iron i can probably melt it and replace the wires...so I just want to solder the new wires with the same quality solder lead use by the factory.

A 30watt iron is on the low side.. personally I have gotten away with a decent 40watt iron from Sears/Craftsman.. best thing is that its only $10..

If you want higher temp solder, you can use the more eco-friendly "no-lead" solder, but its a pain to deal with. You will need a much higher temp iron. If you want a "better quality", look for what they call "silver solder". Costs a bit more than the typical rosin-core lead/tin solder too.. It looks shinier, but also takes a higher quality iron to heat it up the best. Silver solder also doesnt mix well with the lead/tin solder... so beware.

You would probably do better just getting a hotter iron with a good tip. I've done well with the Craftsman for a number of years.. tips are only $3 a set and they even take the iron back if the iron (not the tips) fails.

Jerome

Think you may be concluding the esc has higher temp solder cause your iron can't melt it when its really just the iron. The mass of what you're soldering affects how much heat gets to the solder vs pulled away to heat the entire object up.

Try a higher wattage soldering iron with a good sized chisel shaped tip.

Absolutely right, the solder that R/C manufacturers use is no different than what most electronics manufacturers use(I should know because I've worked in the electronics industry for over 15 years). Really all you need is a decent solder like Kester's 63/37(which is what we use where I work building sensor tools that are used in mine shafts), a good iron(I'd say 40watt bare minimum with a big chisel tip that can transfer the heat very quickly, & more wattage helps even more) & some practice, & you'll have solder joints that will NEVER break down in normal use....

Thanks for the input so far guys....I ll try the more powerful and better iron.