I've seen people wanting gear oil in crank to slow leaks(not realizing that thicker than gear lube mo is easier to obtain) This is backwards.
Before the "out-of-spec" condemning nazis pop a vessel hear me out.
Reason for this seemingly stupid question is cost, of course. I have a 95 Cherokee which is not exactly stock. The point of interest is the rear end, which is a 97(?) Ford 8.8 posi. all fine and good but I have a Riddler diff cover (+>1qt) and my caster is probably + 30° over stock, if not more, making and endless oil pit. When I first installed the rear end I had (so I thought) more than enough oil. 1 qt of M1(20$) a qt of some other syn, and a half gal of Lucas OS (had to be used for something). After all that went in I had to look for more in the garage (qt80-90 house brand). And I ended up dumping 5w30 castrol (God knows how much) to try to fill...then gave up.
Anyway...Checked the oil and it looks dark and should go. Not milky though water content should be high due to mud and water play.
Changing gear lube even at 5$/qt for (pseudo)syn delo (cheapest available to me) I'm looking at a lot of coin.
Tech (overthinking comes in here) data.
Delo 75w90 gl5 sits at 106/14.9 at 40/100c...Amsoil 129.7/16.6 at 40/100.
Delo 400LE 15w40 that I can get for 12-13$ a gallon (if not less) sits at 125/15.2 at 40/100c.
With this in mind viscosity is not something I'm worried about, and for shear stability the amount should help.
My tipping point was to VOA's of gear lube.phos of 1000 give or take and >500ppm of boron.
I will be dumping the "sump" one more time to swap clutches in the near future. Any heavy water play would require an oil change as well. If this was the front diff ( and not the Heep) I'd put in whatever. I run 5w40 T6 in the tranny and it works great. Temps are even better according to my hand/shifter tempermeter (half as warm to the touch) than with GL4 (or 5 I can't tell the difference by smell that well).
I'm a skeptic. Spec made by manufacturers are made to adhere to Gooberment regulations that usually apply to the war for profit. Fuel economy I believe is an excuse to turn a 500k mile prius into a 250k mile pos (based on a complaint by taxi company correlating to the 5w-30 to 0w-20 change).
I have no clue how good the boron is as EP, but based on viscosity alone using HDEO is a no brainer.
PS: As for shear stability the Delo will go through the ultimate test -- the shared sump of my 04 YZF-R1. T6 can't handle it for long (though the "power up" was like I'm in a Super Mario game) That will probably make up my mind (at least to try it)
Before the "out-of-spec" condemning nazis pop a vessel hear me out.
Reason for this seemingly stupid question is cost, of course. I have a 95 Cherokee which is not exactly stock. The point of interest is the rear end, which is a 97(?) Ford 8.8 posi. all fine and good but I have a Riddler diff cover (+>1qt) and my caster is probably + 30° over stock, if not more, making and endless oil pit. When I first installed the rear end I had (so I thought) more than enough oil. 1 qt of M1(20$) a qt of some other syn, and a half gal of Lucas OS (had to be used for something). After all that went in I had to look for more in the garage (qt80-90 house brand). And I ended up dumping 5w30 castrol (God knows how much) to try to fill...then gave up.
Anyway...Checked the oil and it looks dark and should go. Not milky though water content should be high due to mud and water play.
Changing gear lube even at 5$/qt for (pseudo)syn delo (cheapest available to me) I'm looking at a lot of coin.
Tech (overthinking comes in here) data.
Delo 75w90 gl5 sits at 106/14.9 at 40/100c...Amsoil 129.7/16.6 at 40/100.
Delo 400LE 15w40 that I can get for 12-13$ a gallon (if not less) sits at 125/15.2 at 40/100c.
With this in mind viscosity is not something I'm worried about, and for shear stability the amount should help.
My tipping point was to VOA's of gear lube.phos of 1000 give or take and >500ppm of boron.
I will be dumping the "sump" one more time to swap clutches in the near future. Any heavy water play would require an oil change as well. If this was the front diff ( and not the Heep) I'd put in whatever. I run 5w40 T6 in the tranny and it works great. Temps are even better according to my hand/shifter tempermeter (half as warm to the touch) than with GL4 (or 5 I can't tell the difference by smell that well).
I'm a skeptic. Spec made by manufacturers are made to adhere to Gooberment regulations that usually apply to the war for profit. Fuel economy I believe is an excuse to turn a 500k mile prius into a 250k mile pos (based on a complaint by taxi company correlating to the 5w-30 to 0w-20 change).
I have no clue how good the boron is as EP, but based on viscosity alone using HDEO is a no brainer.
PS: As for shear stability the Delo will go through the ultimate test -- the shared sump of my 04 YZF-R1. T6 can't handle it for long (though the "power up" was like I'm in a Super Mario game) That will probably make up my mind (at least to try it)
Last edited:
