Changing the Axle Oil?

My rodeo is approaching the 60K mile marker and I am debating on the wisdom of changing the axle oil again (I did it once at 30K miles.) The owners manual recommends doing it every 30 K miles. But all other non Isuzu service shops I've consulted said that most vehicles never need that done before 120K miles. Some said that they had had 4wd vehicles they regularly maintained into 200K mile range that never had nor needed the axle oil changed? Is this a necessary maintenance or is just another way to spend several hundred bucks that I don't have?

Thanks
Andy

Andy- A typical dealer charge for a front & rear axle lube changeout is under $100. The rear axle requires a tube of limited slip additive that I would not get anywhere but from an isuzu dealer. The axles are covered under the 10yr/120Kmi warranty, so if you ever have an issue with them, the dealer may want to see proof of maintenance. You can make this a fairly easy DIY project & save the receipts, but the dealer will pull the rear diff. cover & do a thourough job for you. This is one of those jobs I don't mind paying the dealer to do for me!
G/luck
Joel

This is one of those jobs that I know my buddy would say, "Change the fluid - what for?" Flipping through the Haynes manual, though, it looks like an easy job. I think I'm going to treat the Rodeo to a tranny fluid and filter change, and an axle oil change this holiday weekend.

You have a Haynes Manual for a late model Rodeo? (2000+?) If so, where did you find it? I called the usual suspects looking for one, Pep Boys, Auto Zone, local bookstore and Library. no luck.

I think I'm entering the post warranty phase when a rodeo shop book would be real helpful.

i found a Haynes at autozone maybe ask them to order you one its worth a shot

Yeah. It was either Autozone or Discount.

But mine is a '97...

What is the skinny on the limited slip additive. I jsut changed mine and used MOBIL 1 synthetic