Supertech synthetic gear oil 75W-90

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Feb 21, 2008
I know Severe Gear is good, blah, blah, blah.....does anyone know this oil or use it in their HD trucks? Hoping Dave or Arkapig might chime in here....thanks!
Nevermind...been reading about it after finally finding it searching around. I did not find any good reports for heavy duty use (towing, etc...) like I will be doing. Gonna see if I can find a Napa close enough to get some Severe Gear. Go ahead Amsoil junkies....pipe in if you must. shocked laugh
ANDA this is in the wrong section....whoopsadaisy!! I am so used to posting in this section. Sorry moderators!!
I am not sure how it would hold up to heavy towing, but I have never heard of someones transfer case or engine blowing up because of Super Tech products.
Check the label on SuperTech 75w-90. I believe it is a synthetic blend, not a full synthetic. I used it for a flush cycle on my truck when I first bought it and after draining it out in less than 10,000 miles, it looked awful (worse than the fluid with an unknown history originally drained) and there was definitely less of a load on my truck engine when changing to Amsoil Severe Gear. If you're looking to save money, try Castrol Syntec 75w-90. That's about $10 a bottle. I've never used it, but I don't think it would be a bad fluid, seeing that Castrol makes it.
In the Dmax/HD trucks, the OEM of the diff (Eaton) specifically has stated that any GL-5 will suffice, be it dino or syn. Obviously syns are going to take a bit of heat a bit better and last a bit longer. The AAM axle with the Eaton diffs have been known to not overheat even under towing conditions as long as the diff is kept at proper fill levels. I personally hammered my truck about as hard as I could this summer (see my UOA) and I used Synpower in the rear this year. No issues whatsoever. Since the ST oil is GL-5 rated, I'd suspect it will do just fine. I have posted some related links over at DP many, many times. Please review them when you get a chance. I have posted many links and quoted my sources, as always. One of which is a direct quote from an Eaton representative about GL-5 being the effitive good choice, regardless of brand/base stock. BTW - nice to hear from you, Byron. Long time; too long.
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Thanks for the chime in guys. And Dave, definitely too long! In Paramedic school, became a dad, and all of that life stuff, but it's time for me to get back to my lube-geek roots. It just feels so right smile I'll check out those other resources. I am pretty curious. I'll be coming back around more often. Good to be here.
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