Recent Topics
Castrol Classic Water Pump Grease
by Buick8
12/05/16 08:25 AM
Low temperature startability and pumping...
by Shannow
12/05/16 04:25 AM
Silverado Vent popping/growling noise
by Georgiey22
12/05/16 02:23 AM
Oil For Mazdaspeed3 2.3 Turbo?
by DoubleWasp
12/05/16 01:06 AM
Glock Trigger Work
by BlueOvalFitter
12/05/16 12:28 AM
Old sled fixer upper
by buck91
12/05/16 12:08 AM
It's Just An Oil Filter
by BlueOvalFitter
12/04/16 10:33 PM
1971 Citroen SM
by FordBroncoVWJeta
12/04/16 10:14 PM
Fortin and Idatalink remote starts
by leeaspell
12/04/16 10:13 PM
Is any one familiar with calif gun laws?
by Chris142
12/04/16 10:13 PM
student loan relief
by bmwjohn
12/04/16 10:08 PM
Driving less, anything to keep car in good shape?
by NoNameJoe
12/04/16 10:04 PM
Newest Members
johny, captearlg, SkipH, DweezilAZ, Kylehorse
59782 Registered Users
Who's Online
85 registered (AKA, 4WD, AirgunSavant, 46Harry, 2004tdigls, 05LGTLtd, 7 invisible), 1617 Guests and 28 Spiders online.
Key: Admin, Global Mod, Mod
Forum Stats
59782 Members
66 Forums
257877 Topics
4242096 Posts

Max Online: 2862 @ 07/07/14 03:10 PM
Donate to BITOG
Topic Options
#2417308 - 10/26/11 07:50 PM 1998 z71 front &rear diff's
Jaybird79 Offline


Registered: 11/01/10
Posts: 7
Loc: Illinois
Hi does anybody know if i can run Mobil 1 75w90 in both the front and rear differentials in this truck? Also do i need to put any LS additive in either one,it does have the Eaton G80 in the rear.

Top
#2418125 - 10/27/11 05:45 PM Re: 1998 z71 front &rear diff's [Re: Jaybird79]
artificialist Offline


Registered: 09/23/07
Posts: 8356
Loc: Florida
What does your owner's manual say your truck needs?
_________________________
2010 Lancer Ralliart Sportback

Top
#2418283 - 10/27/11 08:40 PM Re: 1998 z71 front &rear diff's [Re: Jaybird79]
Fazzone Offline


Registered: 08/17/09
Posts: 104
Loc: Mondovi Wisconsin
Yes, you should be fine. I had no issues in my last truck('98 GMC 1500 Z71) running it. As far as the LS additive, mine didn't need it, but I don't recall specifically which rear end was in it. The manual specs call for conventional in the front, but if you want to spend the extra $ go for it.
_________________________
2012 GMC 2500 HD

Top
#2418285 - 10/27/11 08:40 PM Re: 1998 z71 front &rear diff's [Re: Jaybird79]
Jaybird79 Offline


Registered: 11/01/10
Posts: 7
Loc: Illinois
SAE 80w90 GL-5 gear oil front and rear.

Top
#2418463 - 10/28/11 05:55 AM Re: 1998 z71 front &rear diff's [Re: Jaybird79]
NHHEMI Offline


Registered: 07/06/07
Posts: 6382
Loc: NH
Originally Posted By: Jaybird79
Hi does anybody know if i can run Mobil 1 75w90 in both the front and rear differentials in this truck? Also do i need to put any LS additive in either one,it does have the Eaton G80 in the rear.


You can run 75W90 synthetic in both and it would be an upgrade. No LS additive required with the G80 but if the fluid you select has it don't worry. It will still work fine.
_________________________
Proud user of Royal Purple products thumbsup

Top
#2418503 - 10/28/11 07:49 AM Re: 1998 z71 front &rear diff's [Re: Jaybird79]
Jaybird79 Offline


Registered: 11/01/10
Posts: 7
Loc: Illinois
Thanks NHHEMI, just wanted make sure it would be okay. I can get the mobil 1 for about $4.00 a qt at AAP so I thought why not upgrade.

Top
#2419234 - 10/28/11 09:25 PM Re: 1998 z71 front &rear diff's [Re: Jaybird79]
wtd Offline


Registered: 06/25/02
Posts: 1656
Loc: southwest Mo.
I run shell coventional 80W-90 gear oil in my 98 Z71 but used to run Mobil 1 in both diffs. It might just be a coincidence but I had to have my rear end rebuilt at 75,000 miles with hardly any towing or hauling. After that I went back to conventional and now at 120,000 miles, no problems. I first started hearing noises at about 55,000 miles but could not figure out what it was and finally had it looked at professionally which ended up with the repair. Others have had good luck with it so for that price you might as well try it.

Wayne
_________________________
2014 Mustang GT
1998 Chevy K3500
1998 Chevy K1500
(2) 1992 Cavaliers
1970 Monte Carlo

Top