Originally Posted by
rpgdeity
Add to the problem trying to spin them at high rates of speeds with 5.88 gearing and 34" tires will certainly cook at 200. The gear ratio you are running with those tires is much better.
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There is probably 99% of the problem, but.........I rebuilt my NP200, hot tanked and thoroughly cleaned the empty case, replaced all the bearings and seals, then set the preload perfectly. It still overheats after any extended driving over 50 MPH.
Now, many members have installed NP205's in stock trucks without doing anything to the 205, which probably had more miles than any 200 ever saw, and instantly eliminated the heat issue. Certainly must be a design difference of some sort.
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