[chester_]

Had to take the ole JK in for a check engine light. Turns out just the oil pressure sensor had gone bad but while the dealer had it I get a call saying its time to flush the front and rear axles and flush the transfer case. I'm no wrench turner so I have no idea. Told them I'd hold off and schedule something another time. Got 15000 miles so is it time to have this done?

 

[mhicanders]

Your owners manual should have all that information in it. Change intervals can change model year to model year. As far as 'flush' I've never known anyone to flush anything except radiators and automatic transmissions. Usually front and rear diffs, transfer cases and manual transmissions just get an oil change and the intervals are usually pretty high (some manual transmission call for 100k intervals).

 

[kik]

If you pretty much drive normally, it doesn't need to be done. Huge profit margin for the dealer. Hold off at least another 15,000 miles and have a reputable local shop do it if you don't want to tackle it. You'll pay double for the dealer to do it.

 

[TrueNorth]

Diff service at 15,000???

They recommend you change your oil every 1500 miles too?

Your dealership is trying to rip you off.

Find a local ASE certified mechanic for fluid changes and regular service.

 

[al_safety]

I changed my diff fluid at 18k miles. Rear diff was black, with a ton of crud sticking to the drain plug. I will change again after 15k more miles. Since the diffs have drain plugs, it's fairly easy to service yourself. At next change I plan on pulling the covers, to see wear pattern.

 

[ScarletVarlet]

Generally I favor changing the first engine oil at no more than 1,500 miles. Those first 1,500 should be driven easy as you are breaking in the engine and establishing wear patterns. Hard driving may see you chased by a blue cloud earlier than you like.

As there's no combustion in axles or transmissions I think the impact should be considerably lower, though it may not be a bad idea to change oil/fluid within 30,000 miles and then you can probably wait 100K for the next.

Seeing black gunk coming out doesn't sound promising. I wonder if your rear diff is running hot and turning some of the oil to carbon. If that's the case you'll be experiencing some serious wear. Should have that checked out.

 

[Vt rider]

I know that my Silverado 4x4 has the transfer case fluid changed every 24K miles. It's the only maintenance other than oil changes that has to be done. Everything else is around 100K. It's fairly inexpensive and IMHO, worth doing.