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Your take on mixing brands of rear end oils.

Cranky

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Brands in question is Pennzoil and O'Reillys. Who makes the O'Reillys oil? Never have been one that cared to mix brands but is regular 80w-90 GL-5 all that different from brand to brand? The problem I'm having is my LSD is chattering in my Dana 70 with Mobil 1 Syn with the friction modifier already in it and wanted to try it with regular oil and Mopar modifier. 2 quarts are in it but it needs 3 but may run it with the 2 in it just to see if it quits chattering. I have one qt of the Pennzoil on the shelf and thought may as well use it......
 
Did you do the figure eights in a parking lot to activate the clutches? That helps to get the oil into the clutch disks. (But you know this)

Maybe try non synthetic?
 
I really don't think there is any difference in the 80W90 GL5 gear lub. They all have to meet the specifications. Synthetic is a different story IMO. I don't believe in running synthetic gear lub in our old iron. That's my take.
 
Agree with above, maybe I'm just old school, but have stuck with non-synthetic. I've tried various additives in the sure-grip and folks have their takes on mopar, ford, gm. I've used them all...last fill was gm stuff and seems fine.
 
I really don't think there is any difference in the 80W90 GL5 gear lub. They all have to meet the specifications. Synthetic is a different story IMO. I don't believe in running synthetic gear lub in our old iron. That's my take.
Differ there syns are not bad old way straight 30 for the motor transmissions are a different thing its all design nice thing is all of can learn.
 
Did you do the figure eights in a parking lot to activate the clutches? That helps to get the oil into the clutch disks. (But you know this)

Maybe try non synthetic?
Did half 8's lol. I live on a Culture da Suck and it's not big enough to do the full figure 8's. It seems to be better but need to go ahead and fill it on up, register the thing and drive it more to get some heat into it. Just so dang hot right now. It's finally cooling off a bit...95 from 97. When it gets this hot, 3 degrees makes a difference! Before, it made the truck shudder and it's not doing that now thank God! Btw, it has non syn in it now.
 
Did half 8's lol. I live on a Culture da Suck and it's not big enough to do the full figure 8's. It seems to be better but need to go ahead and fill it on up, register the thing and drive it more to get some heat into it. Just so dang hot right now. It's finally cooling off a bit...95 from 97. When it gets this hot, 3 degrees makes a difference! Before, it made the truck shudder and it's not doing that now thank God! Btw, it has non syn in it now.
Dang you know this all too well.
 
Did half 8's lol. I live on a Culture da Suck and it's not big enough to do the full figure 8's. It seems to be better but need to go ahead and fill it on up, register the thing and drive it more to get some heat into it. Just so dang hot right now. It's finally cooling off a bit...95 from 97. When it gets this hot, 3 degrees makes a difference! Before, it made the truck shudder and it's not doing that now thank God! Btw, it has non syn in it now.
**** sorry i didnt answer oil is oil just depends how the old viscosity flows there are so many like today just rebuilt an old jeep 231 transfercase and it needed Mercon.
 
Did half 8's lol. I live on a Culture da Suck and it's not big enough to do the full figure 8's. It seems to be better but need to go ahead and fill it on up, register the thing and drive it more to get some heat into it. Just so dang hot right now. It's finally cooling off a bit...95 from 97. When it gets this hot, 3 degrees makes a difference! Before, it made the truck shudder and it's not doing that now thank God! Btw, it has non syn in it now.
You are learning now my hat is off to you.
 
Did half 8's lol. I live on a Culture da Suck and it's not big enough to do the full figure 8's. It seems to be better but need to go ahead and fill it on up, register the thing and drive it more to get some heat into it. Just so dang hot right now. It's finally cooling off a bit...95 from 97. When it gets this hot, 3 degrees makes a difference! Before, it made the truck shudder and it's not doing that now thank God! Btw, it has non syn in it now.
You are my age for sure keep kickin *** brother.
 
I've had lockers that would quiet down with a fluid change, others demanded additive. Still use GL5.
My go to additive is IH brand
 
You are my age for sure keep kickin *** brother.
The heat is kickin my *** more than I'm kickin anything lol but I'm still out in the shop. It's 93 now and I'm hearing some heavy thunder not too far away. Still have bright sunshine too. Go figure.
 
The heat is kickin my *** more than I'm kickin anything lol but I'm still out in the shop. It's 93 now and I'm hearing some heavy thunder not too far away. Still have bright sunshine too. Go figure.
Time to move inside and kick the A/C
 
Took the Runner out today and it is 104. Iwould run any of the oils you mention with the Ford additive. The only thing that chatters are my teeth when its below freezing.
 
maybe a different additive/blend in different brands
for just a street beater with a limited slip
I'd not worry much
especially if they are the same viscosity

I don't think mixing dino oil & synthetics is a good idea ever

I had changed to all synthetics in my 99 Dakota SLT 4x4
all Royal Purple stuff, so far so good
I don't put enough miles on it to see any real difference "yet"
the truck has only lil' over 60k original miles
it was 20 years old & IMO it needed to be changed

shocking thing is
it didn't smell like used gear oil does & was still really green
it had whatever Dodge put in it & it was checked regularly
I had never added any (didn't need it)
unless it's warranty 7/70 service it was addressed
or they may have added some (I don't remember seeing it on any tag)
hasn't been to someone else to service
in 13-14 years now (like 2006)
I never added any,
checked whenever did tire rotation or engine oil changes
never added until I did the change over to RP synthetic
it was full, when I drained it...

My 02 F350 4x4 5 speed dually still uses the dino oil,
I have a crapload from Shell, Spirax S6 75-90w IIRC
it has limited slips front & rear too
it's what it came with from the factory & when it was serviced
it's going on 175k (IIRC) miles so far so good
 
The heat is kickin my *** more than I'm kickin anything lol but I'm still out in the shop. It's 93 now and I'm hearing some heavy thunder not too far away. Still have bright sunshine too. Go figure.
Best way is just suck it up butter cup.
 
maybe a different additive/blend in different brands
for just a street beater with a limited slip
I'd not worry much
especially if they are the same viscosity

I don't think mixing dino oil & synthetics is a good idea ever

I had changed to all synthetics in my 99 Dakota SLT 4x4
all Royal Purple stuff, so far so good
I don't put enough miles on it to see any real difference "yet"
the truck has only lil' over 60k original miles
it was 20 years old & IMO it needed to be changed

shocking thing is
it didn't smell like used gear oil does & was still really green
it had whatever Dodge put in it & it was checked regularly
I had never added any (didn't need it)
unless it's warranty 7/70 service it was addressed
or they may have added some (I don't remember seeing it on any tag)
hasn't been to someone else to service
in 13-14 years now (like 2006)
I never added any,
checked whenever did tire rotation or engine oil changes
never added until I did the change over to RP synthetic
it was full, when I drained it...

My 02 F350 4x4 5 speed dually still uses the dino oil,
I have a crapload from Shell, Spirax S6 75-90w IIRC
it has limited slips front & rear too
it's what it came with from the factory & when it was serviced
it's going on 175k (IIRC) miles so far so good
Its all matience with proper oils on the longevity.
 
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