It's probably high resistance in the starter windings, which increase when hot. A good rule of thumb is to never ever install cheap electrical parts on your vehicles. Pep boys and auto-zone are ok on some mechanical items, but I have seen too many folks burned on the electrical parts. Sure it's life time warranty, but how many times do you want to remove and replace the part. I would say this is just my 2 cents, but instead it's my professional opinion and experience.

John


John Luttrell
2001 4x4 short cab, 3 inch lift with 33 inch mudders and Powertrax no-slip in the rear


1991 Jeep YJ, 4 inch suspension lift on 33" BFG's