Jump to content

Front And Rear Diff Fluid Change

chechem1984

Recommended Posts

chechem1984 Enthusiast

chechem1984

Posted
Posted

I have a 2500Hd 6.0 and I need to change the diff fluid front and rear. I was wondering if there is a drain and fill plug on the front diff, or if I have to pull the cover? I know there wasnt a drain plug on the rear, but I need to take the cover off anyways because the fluid is black and gritty, I think the pinion bearing is shot as I get a hum at highway speeds, and the rear end did hitch a couple weeks ago at takeoff. Also, should I be using 75-90 synth in both the front and rear and how many quarts of each? I live in maine and its a cold climate in the winter. I usually only tow snomowbiles for the heaviest load as well. What about super tech gear oil? Are they any good?

smiledr996s Enthusiast

smiledr996s

Posted
Posted
I have a 2500Hd 6.0 and I need to change the diff fluid front and rear. I was wondering if there is a drain and fill plug on the front diff, or if I have to pull the cover? I know there wasnt a drain plug on the rear, but I need to take the cover off anyways because the fluid is black and gritty, I think the pinion bearing is shot as I get a hum at highway speeds, and the rear end did hitch a couple weeks ago at takeoff. Also, should I be using 75-90 synth in both the front and rear and how many quarts of each? I live in maine and its a cold climate in the winter. I usually only tow snomowbiles for the heaviest load as well. What about super tech gear oil? Are they any good?

 

 

I just changed mine, yes drain and fill plug on both F & R. The Rear is easy to remove the cover the front would be alot of work. I used Mobile 1 75w-90 LS synthetic. If I remember correctly it was like 2 in front and under 4 in back. Six quarts should be plenty. Not sure about super tech, I am sure it is a rebranded version of Valvoline or pennsoil.

 

Steve

chechem1984 Enthusiast

chechem1984

Posted
  • Author
Posted
I have a 2500Hd 6.0 and I need to change the diff fluid front and rear. I was wondering if there is a drain and fill plug on the front diff, or if I have to pull the cover? I know there wasnt a drain plug on the rear, but I need to take the cover off anyways because the fluid is black and gritty, I think the pinion bearing is shot as I get a hum at highway speeds, and the rear end did hitch a couple weeks ago at takeoff. Also, should I be using 75-90 synth in both the front and rear and how many quarts of each? I live in maine and its a cold climate in the winter. I usually only tow snomowbiles for the heaviest load as well. What about super tech gear oil? Are they any good?

 

 

I just changed mine, yes drain and fill plug on both F & R. The Rear is easy to remove the cover the front would be alot of work. I used Mobile 1 75w-90 LS synthetic. If I remember correctly it was like 2 in front and under 4 in back. Six quarts should be plenty. Not sure about super tech, I am sure it is a rebranded version of Valvoline or pennsoil.

 

Steve

 

 

Is there a drain plug in the front?

chechem1984 Enthusiast

chechem1984

Posted
  • Author
Posted

I bought some super tech synthetic blend 75w-90 gear oil. It says its API GL-5 compt. Will this work with my truck? I do tow snowmobiles with it, but it is parked in a garage in the winter

smiledr996s Enthusiast

smiledr996s

Posted
Posted
I bought some super tech synthetic blend 75w-90 gear oil. It says its API GL-5 compt. Will this work with my truck? I do tow snowmobiles with it, but it is parked in a garage in the winter

 

Probably would, not sure, I like Mobile 1 for most additive I buy locally. Make sure it is for limited slip if you have it, or add a bottle of the GM additive

txdutt Enthusiast

txdutt

Posted
Posted

I just did mine a few months ago--everything from the front diff/transfer case/tranny/rear diff...read the bottle very carefully on the gear lube to see if it needs the LS additive or not, the Mobil1 stuff didn't that I bought...

chechem1984 Enthusiast

chechem1984

Posted
  • Author
Posted

just called GM and they said its 80/90 non synth in the front. I have 2 quarts of 75/90 synth blend and another 80/90 of regular. I will top the front off with the 80/90 if it needs it. I will also run full synth in the back, prob mobile 1.

 

Thanks,

Black02Silverado Senior Enthusiast

Black02Silverado

Posted
Posted

You can run 75w-90 in both the front and rear diff's. It will run just fine in both. If you plan on using four wheel drive at all in the winter then a synthetic is recommended for the front as well. It will help with engagement and keeping things lubricated when the temp dips down low.

 

The truck came with synthetic in the rear differential from the factory. I would go back with synthetic and not a blend. It will provide better protection and the cost isn't really that much more. 6qts will provide enough to do both the front and the rear. As for an additive it depends on what you have in the rear diff.

dlstewart01 Senior Enthusiast

dlstewart01

Posted
Posted

The truck came with synthetic in the rear differential from the factory. I would go back with synthetic and not a blend. It will provide better protection and the cost isn't really that much more. 6qts will provide enough to do both the front and the rear. As for an additive it depends on what you have in the rear diff.

 

 

There is no factory diff in a full size GM truck that requires an additive,,,,, with the exception of quadrasteer which could be had with a G86 limited slip. That one required an additive.

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Latest Articles

  • Posts

    • PhilB
      Gas Prices

      By PhilB · Posted

      This again?   https://www.reuters.com/fact-check/us-capitol-attack-rioters-had-weapons-including-firearms-2025-01-16/   Think Reuters is biased?  Check their rating https://mediabiasfactcheck.com/reuters/  
    • Thanusdoss
      New car smell air freshener

      By Thanusdoss · Posted

      I found an odor eliminator spray that neutralizes unwanted smells pretty well. Using it with the car's AC running helps to distribute it evenly around the cabin.
    • Atlas
      Gas Prices

      By Atlas · Posted

      WTI futures / speculation is just that. WTI futures <> current 4-7% inflation and national average gas price over $4.00/gallon.   The spot price, at delivery, is currently $87-$95/barrel which is why gas prices remain high.   Edit: oH mY gOd mEnTaL BrEaKdoWn In tHE pOsT aBOve mInE. TrUmpErS goNnA tRumP
    • Jsdirt
      Gas Prices

      By Jsdirt · Posted

      He does, actually. In another unrelated video he mentions the president called him in the middle of the night to relay some information on a cause (religious based) that he's invested in. Glenn expressed concern that another leftist administration could wield too much power with some procedure the Pentagon was using, classifying certain religions a certain way. Being that he is LDS (Latter Day Saints), he gets hate all the time from ALL over the political spectrum, so he's invested in this. Trump called him back at 5AM to tell him he had made some changes to that classification.   So, yes, they are and have been in contact regularly since the start of the administration. Glenn, of course, always asks his permission before discussing anything on the air.   I already spent an hour or more just searching for these videos. I may have my numbers wrong - I'm not a numbers guy. It may have been a MILLION barrels, not 1.5. The point is, our President, by his actions, gives a crap about America, and US - this is completely OPPOSITE the actions of the prior administration who projected hatred for anyone who wasn't following the left's edicts in lock-step.   Remember, they called January 6th an "Insurrection", when there were ZERO weapons among the crowd, undercover FBI agents agitating the crowd, along with paid leftists acting as aggressors, egging the crowd on in an attempt to whip everyone into a frenzy. It's all been proven.  Pelosi refused Trumps request for more National Guard troops. This smells 100% like an inside job for those with critical thinking skills. Only a handful of guys in the crowd got wrapped up in that, thankfully, but EVERYONE was searched out based on cell phone data, and charges were brought against many. And 6 or so people were locked up and left in solitary confinement for YEARS with ZERO due process!! If you give the slightest crap about our Nation, REGARDLESS of your political leanings, this should frighten you to your core. This is what men suffered, bled, fought, and died against 250 years ago!   This has gone FAR BEYOND left vs. right. This is a  threat to America, and our way of life. This is PRECISELY why Trump, a BILLIONAIRE who could have chosen to take Melania and sit on some tropical island that he could afford to buy himself and RELAX, instead chose to run for office, get hate from literally every corner of the media, get ATTEMPTS on his LIFE constantly, and begin to repair some of the severe damage that's been done to this Great Nation.   I don't know why I bother wasting my precious time here. Everyone has their minds made up. They won't realize we all were correct until it's too late ... after they elect another tyrant that hates America to office (Obama), or another puppet whose administration is secretly running the show behind the scenes (Biden).
    • Newduramaxh*ar
      DTC P2C48 auxiliary cooling pump

      By Newduramaxh*ar · Posted

      Hello, Im in a bit of a bind maybe someone could help me out.  We towed our trailer, up a pretty steep incline (395 north of Bishop) done it before no issues. I got to our campground turn truck off, i restarted the truck about an hour later  and check engine light turns on. Found DTC P2C48,  unable to reset.  This morning i removed the plug, there's 12.12v at the plug. Reservoir near firewall is full of coolant, checked for leaks nothing. I dont hear or feel the pump turning on. My dilemma, is nearest dealer  is 4hrs away that has the pump instock. Is it safe to drive? By me checking the available voltage at the connector and not hearing/feeling pump turn on, is it a bad pump? Please help...

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...