I actually pop mine into 6th when cruising at 45 and above just to keep the rpms low and save gas, i've also noticed that when cruising around 3k in the city in 5th, my oil temp gets higher than i'd like.
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2011 Mustang 5.0 | 3.55's | Lethal Performance off road H-Pipe | Magnaflow Muffler Delete | JLT CAI/Bama tuned 417whp/ 404 ft/lbs
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