Ive got a shade over 9,000 miles on this fluid and its starting to get slightly darker red. Still smells good, not burnt smelling or anything like that just getting darker red. Harder to see through it while on the dipstick. Trying not to be over alarmed just want clarification that this is normal??? Any one else know this. See sig. for transmission mods, also it has Mopar ATF + 4 in it. Thanks.