Changing the diff grease (front & rear) at 60,000 miles (highway miles) and was curious what my owners manual shows for the service interval. I’m not a smart person so there is that…. Can’t find anything at all about the recommended mileage. Just the type of gear oil. What am I missing?
2017 GMC Sierra 1500 - Diff Oil Change
- Thread starter PontiacHO
- Start date
I asked my mechanic, he said 100k miles for that and the transmission fluid under normal use. (Well, for my 2016 model, I assume no changes to 2017)
4WD
$50 site donor 2024
Do what you like … here is my 2017 at 17k … changing at 50k it was pristine (Delvac 1)
FF a
4WD
$50 site donor 2024
Just look at the difference in Mopar (standard term for who owns them this year) and ZF on fluid life …
(I will take ZF’s number any day)
It's not what makes us feel better it's what's best for the gears . A early change to get the break in junk out then 30k or so after .
Pretty much any axle available today will easily survive the warranty period on factory oil, that's why they keep the recommendations for replacement at seemingly high mileages.
Change it if it makes you feel better (I change mine) but most half ton and smaller trucks probably head to the junk yard with factory diff oil and the reason they're at the junk yard probably has nothing to do with the axles.
Change it if it makes you feel better (I change mine) but most half ton and smaller trucks probably head to the junk yard with factory diff oil and the reason they're at the junk yard probably has nothing to do with the axles.
I've been told by my GM techs they don't touch it till over 100k which I think is hogwash judging by how often we rebuild them. Rarely gets recommended on 1500s though, mostly 2500/3500s. The severe service chart is the only one that lists to change the fluid trans fluid at all, odd.
In all honesty, if you don't want issues just change everything now, diffs, tcase, and trans especially if you have a 6L80...just do it, the 4wd 6L80s like to blow up if not tended to sooner than later (front pump grenades).
4WD
$50 site donor 2024
It could be - was thixotropic enough to think there was plenty of surface tension caused by high particle count - perhaps some in colloid state if not metal … But as stated - once flushed and the new synthetic took over - was great.
(I did drain a few ounces after 10k and it was a mint sample) …
By contrast - my AdvanTek axles - known metal shedders - had shiny oil with lots of glitter - but the viscosity did not seem effected at all …
4WD
$50 site donor 2024
Obviously you never lost one 2k out of warranty due to lube failure - I did - and not cheap - put in a used one with 20k more than the truck had … Not a good feeling you will forget … Bob’s brand went in that one !
Most if not all GM rear truck diffs have a magnet inside. Typically there can either be a particle infused mung that is magnetic or even shards of metal in some cases. I like to drain the diff and clean that magnet up. I use 50,000 miles as my interval and now have 225,000 miles on the original 14 bolt diff in my 3/4 ton.
Sounds like a reasonable plan.
That’s the plan. Still can’t wrap my mind around why an auto maker (GM) wouldn’t list an interval if nothing else to increase their bottom line in the service department…
On the other hand the owners manual for the last F150 I owned (2003) stated that the factory fill was “lifetime fluid”. Changed at 90,000 and it was still golden/clear. Oh well. Better safe than sorry & broke.
Unless your diff is limited slip you can pretty much use whatever off the shelf stuff you want at Walmart. You could use a thicker oil to protect a bit more but if you're doing more highway cruising and don't tow or haul anything or drive it like you stole it the thinner stuff should be just fine. 60k is kinda early but it never hurts.
I did mine around 30,000. It was nasty looking and the magnet in the bottom was really fuzzy! I’m happy I changed it when I did.
Rear cover bolts should be 20 ft/lbs
Thanks.
