7.3 powerstrok
Full Access Member
from a cold start outside temp 35 degrees.....after say a 20 mile drive speed 40-50 mph ,whats the temp on youre truck around the pinion housing ,,,cold warm/very warm /hot/??
rear differental temperture???
- Thread starter 7.3 powerstrok
- Start date
justinray
Contributor
Warm at most.
7.3 powerstrok
Full Access Member
hmmm my diff was very warm almost to warm to hold hand on the pinion housing ,,,could the posi clutches generate the heat ??i did have a low tire on one side ?
justinray
Contributor
Difference in tire wear could cause a higher heat, but if fluid is up to par and tires are comparable, with those ambient temps, it should be pretty cool with that short of a drive. Either a fluid issue, or a backlash issue.
7.3 powerstrok
Full Access Member
oh the tire was low on air not thread ....i was thinking about the posi trac clutches ,,i don have any addative in the diff ..
pedro_8149
7.3L Remote Turbo
I have a rear diff temp gauge and reads about 160 driving around the city and on the highway it goes up to about 180 at absolute most. Even while im towing highway or city driving it never gets hotter then 180.
jaluhn83
Full Access Member
From what I've seen 250* seems to be a typical upper limit for most lube oils, so anything under 200-225 should be fine.
Hard to say how hot it actually was, I'd think ~150* from that type of drive and weather wouldn't be abnormal, but 180-200 would.
That being said, if there's any question make sure you have the correct fluid/additives. I think some gear oils don't need the friction modifier additive but I'm not sure. Someone who knows more than I can chime in here.
Hard to say how hot it actually was, I'd think ~150* from that type of drive and weather wouldn't be abnormal, but 180-200 would.
That being said, if there's any question make sure you have the correct fluid/additives. I think some gear oils don't need the friction modifier additive but I'm not sure. Someone who knows more than I can chime in here.
Well in my limited knowledge of lubrication, we need 80/140 weight FULL SYNTHETIC gear oil for the Sterling rear diff.
Most of the new Synthetic gear oils do not require a friction modifier for use in a POSITRACTION differential.
HOWEVER, if you do replace rear diff fluids, always read the label of the product you purchased to see if a modifier is required.
JM2CW
Al
7.3 powerstrok
Full Access Member
very nice truck ,thanks for the response ,nice to have all the right gauges ,you are running 15" rims ?did you have to modify anything ?can you post a pic of the gauge placement .layout
icanfixall
Official GMM hand model
I really have never given this much thought. Now I feel I should be checking it. I do have a lot of back lash in the gears so maybe its time to replace them. Way too many miles of heavy towing on them with no upkeep at all.. Same oil in there probably 14 years now.. I'll bet it smells really horrible too.
Gary....GARY...that's plain BAD...Bad toad....you should know better than that...OMG I can't believe you have not swapped out diff fluid in 14 years...Wow!
I'd say it's time for certain. While at it since you TOW heavy, why not add a http://www.mag-hytec.com/products.htm diff cover, it offers an additional lube capacity and just plain helps cool down that diff.
I can imagine how nice the horses would feel stranded on the road side cause you didn't do ROUTINE maintenance...
Just sayin.....
Al
icanfixall
Official GMM hand model
Yes Al... This is one location that I really never look closely at. I do check the brakes and the universal joint every time I change the engine oil. Or at least I look over the joints and the brakes when I lube the universal back there. Just don't change the fluid back there but do look it over for leaks... Never see any. As I posted.. I think it time to change the gears and the oil back there. I'm still on the fence about 4.11 or 3.73...
It don't matter what fence yer on....change the freakin oil at least!
79jasper
Chickenhawk
I agree with Al. And with all your knowledge Gary, that one really surprises me. 
icanfixall
Official GMM hand model
I can't argue with you guys about neglecting the rear diff oil. Its a cross too heavy for me to bare. Funny how I can be on top of most everything else but not that simple thing. Adding the Mag Hitech cover is an idea I have had for a long time too Al. Just doing it is like just installing my hypermax intercooler. I'm a neglectful person to very few things... Probably lazeness is a big part of that too and no real garage to work in. Now IF... I had a shop like Heath has.. And then add a lift to it.. Wow... There would be no reason to return to the big house for sleep...
