I have a 2005 Jeep Liberty Diesel. The maintenance manual calls for changing front and real axel fluids every 12,500 miles at a cost of several hundred dollars a pop. I don’t understand why this is necessary. I’ve owned 4x4 vehicles for over 40 years and never had to do this at anything near this frequency. I have 35000 miles on the vehicle. Most driving is highway (25% in snowy weather) with quite limited off road driving. Whenever I ask the dealer, the replies are vague - the manual calls for it; you don’t have to if you want to take the risk; it’s best to be on the safe side, etc. Assuming that the engineering is good, why is this degree of routine maintenance really necessary.
Someone here might have the intimate engineering knowledge that would be required to answer this. I don’t. However, I would tend to trust the manufacturer’s maintenance schedule. These days it is more the norm for manufacturer’s to play it too loose with what is best for maintenance so that vehicles can be sold as “low maintenance” items. So, in general, I tend to assume that manufacturer recommendations are too long/too many miles. This is especially so these days with transmissions and cooling systems.
So - mine’s not an expert opinion. But the engineering crew that provided this recommendation had to get it past the marketing and sales divisions and I’d actually assume they had to work hard at doing that. So I’d bet there’s a darn good reason.
Limited slip differentials would benefit from regular drain/refills as would those subject to deep water but I have maintained vehicles that accumulated over 1 million miles that never had the gear lube changed. But things do change and that issue has slipped right past me. And all light duty domestic chunks seem to require that the cover be removed to drain them and that could easily require half an hour or more for each axle
Agree; I had a rear drive Chevy Caprice with Positraction and the manual definitely called for changing the fluid every 12,500 miles and adding the special additive that such a unit needs. Not doing it will make the differential clatter and wear out prematurely.
You Liberty may have similar units.
I’d agree with the dealer’s statement. You should do the fluid changes, but if you want to risk it that is your call.
Your old 4X4’s were basically trucks and the gears were relatively robust compared to your Liberty. Heavier gears weigh more and use more gas, so gears in more modern cars and trucks aren’t as stout as they used to be. This can be OK if the gears are properly lubricated.
As for a Jeep Liberty. This isn’t really a design made for heavy duty off road use to begin with. It might have limited slip differentials. Have you priced out replacing the front differential, rear differential, and the transfer case? I think you are looking at major bucks for any one of them.
Shop local garages for better prices is one option. Learning how to get under the car and change the fluids yourself is another option. At this point you are due for your 3rd change and you haven’t done any to this point. It seems you’d rather gamble on a major repair to save a few bucks on maintenance. Risky, but it is up to you. There was a TV ad years back with a mechanic saying “you can pay me now, or pay me a lot more later”. That applies in this situation.
If you know how to remove spark plugs, and change your own oil, you can change the differential fluid on your truck, and save yourself that several hundred dollars.
I would question the frequency recommended by the owners manual as much as I would question the cost. It is as easy to change this fluid as an oil change, it doesn’t use as much replacement fluid as an oil change and there is no filter to change, so it shouldn’t cost anymore than an oil change.
BTW, what fluid is called for? Is it regular GL4 or GL5 gear oil, ATF or something special?
Also, does your owners manual have separate schedules for normal and heavy use? If so, which schedule are you following?
Why would you question the interval?
The change is not nearly as simple as an oil change. Chrysler differentials require that the rear pan be removed from the differential and a new gasket be applied (rtv) before re-attaching the pan. Which means that all the gasket surfaces have to clean of all lubricant, or you will have seepage. Even if you do it yourself, it’s at least 1 hour to do an axle.
My bad, I meant to say “I would not question the frequency”
One hour still doesn’t add up to “several hundred dollars”
No drain plug? Everyone should know about this before they buy one of these. That would be a deal breaker for me and I would let them know. If Chrysler lost a lot of sales because they cut costs at the owners expense, then they would stop this practice.
Does Consumers Reports know that Chrysler is pulling this on their customers, I’ll bet if CR noted this in any articles on Chrysler products, then Chrysler would find out that the value of their product would drop far more than the cost savings.
All car manufacturers should be taken to task for cutting corners on materials that add up to significantly higher maintenance costs to customers. Axle boots would be a good place to start. Using cheap rubber that cracks and splits in 4 to 5 years costs the customer upwards of $400-800 to replace when the manufacturer could have used a higher grade of rubber or urethane (or silicone) that would last a lot longer.