75W-140 Gear Oil
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I may be wrong but.....I was under the impression that the 75W-140 is used in the rear differential for vehicles that either Tow or Carry very heavy loads.
I just changed out the gear oil in my front diff, rear diff and transfer case in my T4R in July. The OEM spec is for 75W-90 for all three....so they all got a change with Mobil 1, synthetic Gear oil. I do have a spare quart of Mobil 1, 75W-140 that I'll use to top off the rear diff if needed.
I just changed out the gear oil in my front diff, rear diff and transfer case in my T4R in July. The OEM spec is for 75W-90 for all three....so they all got a change with Mobil 1, synthetic Gear oil. I do have a spare quart of Mobil 1, 75W-140 that I'll use to top off the rear diff if needed.
The higher viscosity lube helps with higher diff temps associated with limited slip diffs and/or higher loads during towing.
Yes, Mongo, I could see why in a HD application. The thing is, I've seen it used in LD applications too...
BMWtech: older Explorers, for example, call for 75W-140. It seems overly thick for a vehicle that probably wouldn't be used any harder than the average ride??
BMWtech: older Explorers, for example, call for 75W-140. It seems overly thick for a vehicle that probably wouldn't be used any harder than the average ride??
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The Ford 8.8 rear called for 75w90 until 2001 when every vehicle w/8.8 now called for 75w140. I am not aware of any changes made inside the rear.
Holden calls for 75w140 in their diffs even on the cars. I've run it for that reason. GM NA says that 75w90 is good for the diff now that the friction modifier GM Australia specs is no longer available through the dealer here in the states and the replacement part number is the same 75w90 for the Corvettes. I stick I use Torco RGO 85w140 because I figure there had to be a reason for them to call for the thick stuff.
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Originally Posted By: JasonC
The Ford 8.8 rear called for 75w90 until 2001 when every vehicle w/8.8 now called for 75w140. I am not aware of any changes made inside the rear.
GVWR and horsepower have grown considerably since 2001. To accommodate the heavier GVWR, Ford called for 75W140 to increase reliability.
The Ford 8.8 rear called for 75w90 until 2001 when every vehicle w/8.8 now called for 75w140. I am not aware of any changes made inside the rear.
GVWR and horsepower have grown considerably since 2001. To accommodate the heavier GVWR, Ford called for 75W140 to increase reliability.
Nope, Many Apps for the 8.8 did begin calling for 75W140, others didnt.
My car does says 80W90
My Grandpas Ranger says 80W90 as well.
2001 is also when SAE split the 90 and 140 weights. The top half of 90 became 110 and the top half of 140 became 190. The idea was to give them more flexibility in lubricant selection since each grade is now a narrower range of viscosity. So they wouldnt have to jump up to a 140 if the bottom end of the 90 grade didnt meet durability specifications. They would spec a 110 and get a couple percent better fuel economy than the 140.. In theory.
Problem is, no one makes 110 grade stuff. I think maybe 2 or 3 oils are available in that grade and the Amsoil I have in my diff is one of them.
My car does says 80W90
My Grandpas Ranger says 80W90 as well.
2001 is also when SAE split the 90 and 140 weights. The top half of 90 became 110 and the top half of 140 became 190. The idea was to give them more flexibility in lubricant selection since each grade is now a narrower range of viscosity. So they wouldnt have to jump up to a 140 if the bottom end of the 90 grade didnt meet durability specifications. They would spec a 110 and get a couple percent better fuel economy than the 140.. In theory.
Problem is, no one makes 110 grade stuff. I think maybe 2 or 3 oils are available in that grade and the Amsoil I have in my diff is one of them.
Originally Posted By: JasonC
The Ford 8.8 rear called for 75w90 until 2001 when every vehicle w/8.8 now called for 75w140. I am not aware of any changes made inside the rear.
My 2006 Ranger with 8.8 still calls for 80w90. Only the FX4 models with the Torsen limited slip called for 75w140.
The Ford 8.8 rear called for 75w90 until 2001 when every vehicle w/8.8 now called for 75w140. I am not aware of any changes made inside the rear.
My 2006 Ranger with 8.8 still calls for 80w90. Only the FX4 models with the Torsen limited slip called for 75w140.
Originally Posted By: Torrid
Holden calls for 75w140 in their diffs even on the cars. I've run it for that reason. GM NA says that 75w90 is good for the diff now that the friction modifier GM Australia specs is no longer available through the dealer here in the states and the replacement part number is the same 75w90 for the Corvettes. I stick I use Torco RGO 85w140 because I figure there had to be a reason for them to call for the thick stuff.
I also use a 75W-140, but this is because I have a very noisy, and notoriously weak 7.5" 10 bolt rear axle with over 375 hp, and lb. ft. of torque being pushed through it.
I've actually tried the Amsoil Extreme gear racing stuff (190 weight & 250 weight mixed
), but it either made no difference in noise, or at times actually made the gear scream worse, so I backed down to the SVO oil.
What size is the ring & pinion in the independent rear's center section on the GTO/Monaro, and is it the same as what's under the back of CTS-Vs, and 5th gen f bodies??
Holden calls for 75w140 in their diffs even on the cars. I've run it for that reason. GM NA says that 75w90 is good for the diff now that the friction modifier GM Australia specs is no longer available through the dealer here in the states and the replacement part number is the same 75w90 for the Corvettes. I stick I use Torco RGO 85w140 because I figure there had to be a reason for them to call for the thick stuff.
I also use a 75W-140, but this is because I have a very noisy, and notoriously weak 7.5" 10 bolt rear axle with over 375 hp, and lb. ft. of torque being pushed through it.
I've actually tried the Amsoil Extreme gear racing stuff (190 weight & 250 weight mixed
What size is the ring & pinion in the independent rear's center section on the GTO/Monaro, and is it the same as what's under the back of CTS-Vs, and 5th gen f bodies??
Originally Posted By: Scott88
older Explorers, for example, call for 75W-140. It seems overly thick for a vehicle that probably wouldn't be used any harder than the average ride??
Ford probably got sick of replacing blown-up rears under warranty (had that problem on a couple Explorers).
I run 80W-140 in everything now.
older Explorers, for example, call for 75W-140. It seems overly thick for a vehicle that probably wouldn't be used any harder than the average ride??
Ford probably got sick of replacing blown-up rears under warranty (had that problem on a couple Explorers).
I run 80W-140 in everything now.
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Originally Posted By: dailydriver
Originally Posted By: Torrid
Holden calls for 75w140 in their diffs even on the cars. I've run it for that reason. GM NA says that 75w90 is good for the diff now that the friction modifier GM Australia specs is no longer available through the dealer here in the states and the replacement part number is the same 75w90 for the Corvettes. I stick I use Torco RGO 85w140 because I figure there had to be a reason for them to call for the thick stuff.
I also use a 75W-140, but this is because I have a very noisy, and notoriously weak 7.5" 10 bolt rear axle with over 375 hp, and lb. ft. of torque being pushed through it.
I've actually tried the Amsoil Extreme gear racing stuff (190 weight & 250 weight mixed
), but it either made no difference in noise, or at times actually made the gear scream worse, so I backed down to the SVO oil.
What size is the ring & pinion in the independent rear's center section on the GTO/Monaro, and is it the same as what's under the back of CTS-Vs, and 5th gen f bodies??
The GTO/Monaro diff is a Dana M80. I'm pretty sure it's a 7.75 9 bolt, but it's only rated to around 400bhp so it isn't that tough for higher modified cars.
Originally Posted By: Torrid
Holden calls for 75w140 in their diffs even on the cars. I've run it for that reason. GM NA says that 75w90 is good for the diff now that the friction modifier GM Australia specs is no longer available through the dealer here in the states and the replacement part number is the same 75w90 for the Corvettes. I stick I use Torco RGO 85w140 because I figure there had to be a reason for them to call for the thick stuff.
I also use a 75W-140, but this is because I have a very noisy, and notoriously weak 7.5" 10 bolt rear axle with over 375 hp, and lb. ft. of torque being pushed through it.
I've actually tried the Amsoil Extreme gear racing stuff (190 weight & 250 weight mixed
What size is the ring & pinion in the independent rear's center section on the GTO/Monaro, and is it the same as what's under the back of CTS-Vs, and 5th gen f bodies??
The GTO/Monaro diff is a Dana M80. I'm pretty sure it's a 7.75 9 bolt, but it's only rated to around 400bhp so it isn't that tough for higher modified cars.
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OVERKILL
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Originally Posted By: BubbaFL
Originally Posted By: Scott88
older Explorers, for example, call for 75W-140. It seems overly thick for a vehicle that probably wouldn't be used any harder than the average ride??
Ford probably got sick of replacing blown-up rears under warranty (had that problem on a couple Explorers).
I run 80W-140 in everything now.
I assume these were IRS equipped Explorers and not the old 8.8" straight axle ones, which are generally regarded as indestructible.
Originally Posted By: Scott88
older Explorers, for example, call for 75W-140. It seems overly thick for a vehicle that probably wouldn't be used any harder than the average ride??
Ford probably got sick of replacing blown-up rears under warranty (had that problem on a couple Explorers).
I run 80W-140 in everything now.
I assume these were IRS equipped Explorers and not the old 8.8" straight axle ones, which are generally regarded as indestructible.
OVERKILL
$100 Site Donor 2021
Originally Posted By: BubbaFL
Originally Posted By: OVERK1LL
I assume these were IRS equipped Explorers and not the old 8.8" straight axle ones, which are generally regarded as indestructible.
Second gen Explorers, 8.8" solid rear.
How in the heck did you kill a 31-spline 8.8? Seriously, they hold up well to 500+HP built Mustangs on slicks......
Originally Posted By: OVERK1LL
I assume these were IRS equipped Explorers and not the old 8.8" straight axle ones, which are generally regarded as indestructible.
Second gen Explorers, 8.8" solid rear.
How in the heck did you kill a 31-spline 8.8? Seriously, they hold up well to 500+HP built Mustangs on slicks......
Originally Posted By: OVERK1LL
BubbaFL said:OVERK1LL said:How in the heck did you kill a 31-spline 8.8? Seriously, they hold up well to 500+HP built Mustangs on slicks......
I had two of them go on different Explorers using the original 75w-90 spec gear oil. No problems with them after a rebuild and switching to 85w-140.
Maybe I just had bad luck? Since Ford changed from 75w-90 to 75w-140, I assumed the original spec oil just wasn't good enough.
OVERKILL
$100 Site Donor 2021
Originally Posted By: BubbaFL
Originally Posted By: OVERK1LL
Originally Posted By: OVERK1LL
BubbaFL said:OVERK1LL said:How in the heck did you kill a 31-spline 8.8? Seriously, they hold up well to 500+HP built Mustangs on slicks......
I had two of them go on different Explorers using the original 75w-90 spec gear oil. No problems with them after a rebuild and switching to 85w-140.
Maybe I just had bad luck? Since Ford changed from 75w-90 to 75w-140, I assumed the original spec oil just wasn't good enough.
That's nuts! Even the F-150, Crown Vic, Expedition....etc had the 8.8 in it. Many of those vehicles spec'd the lighter weight lube. I've owned a few of 'em.
Sir, I would agree that you had some bad luck!
Originally Posted By: Torrid
Originally Posted By: dailydriver
Originally Posted By: Torrid
Holden calls for 75w140 in their diffs even on the cars. I've run it for that reason. GM NA says that 75w90 is good for the diff now that the friction modifier GM Australia specs is no longer available through the dealer here in the states and the replacement part number is the same 75w90 for the Corvettes. I stick I use Torco RGO 85w140 because I figure there had to be a reason for them to call for the thick stuff.
I also use a 75W-140, but this is because I have a very noisy, and notoriously weak 7.5" 10 bolt rear axle with over 375 hp, and lb. ft. of torque being pushed through it.
I've actually tried the Amsoil Extreme gear racing stuff (190 weight & 250 weight mixed
), but it either made no difference in noise, or at times actually made the gear scream worse, so I backed down to the SVO oil.
What size is the ring & pinion in the independent rear's center section on the GTO/Monaro, and is it the same as what's under the back of CTS-Vs, and 5th gen f bodies??
The GTO/Monaro diff is a Dana M80. I'm pretty sure it's a 7.75 9 bolt, but it's only rated to around 400bhp so it isn't that tough for higher modified cars.
Has anyone ever tried to adapt the new 9" IRS center section for the 5th gen Camaros from The Driveshaft shop/Hendrix, etc. to the Monaro/GTO IRS for the higher power beasts??
Originally Posted By: dailydriver
Originally Posted By: Torrid
Holden calls for 75w140 in their diffs even on the cars. I've run it for that reason. GM NA says that 75w90 is good for the diff now that the friction modifier GM Australia specs is no longer available through the dealer here in the states and the replacement part number is the same 75w90 for the Corvettes. I stick I use Torco RGO 85w140 because I figure there had to be a reason for them to call for the thick stuff.
I also use a 75W-140, but this is because I have a very noisy, and notoriously weak 7.5" 10 bolt rear axle with over 375 hp, and lb. ft. of torque being pushed through it.
I've actually tried the Amsoil Extreme gear racing stuff (190 weight & 250 weight mixed
What size is the ring & pinion in the independent rear's center section on the GTO/Monaro, and is it the same as what's under the back of CTS-Vs, and 5th gen f bodies??
The GTO/Monaro diff is a Dana M80. I'm pretty sure it's a 7.75 9 bolt, but it's only rated to around 400bhp so it isn't that tough for higher modified cars.
Has anyone ever tried to adapt the new 9" IRS center section for the 5th gen Camaros from The Driveshaft shop/Hendrix, etc. to the Monaro/GTO IRS for the higher power beasts??
i thought the explorer had the 29 spline 8.8. i know my 1994 f-150 has a 31 spline. come to think of it doesnt the mustang have the 29 spline as well? my manual says for ford 90wt in the conventional axles. it say syn 75-140 for the lightning.
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