My niece has been told that her Honda CRV (about 8-9 years old I think) has problems with the rear differential. It was making a bad noise. The fluid was replaced, but she was told that this will no fix the problem permanently, and that there was no fix. 1)is this a safety issue or merely a performance issue? 2) is it fixable, and if so how?
You didn’t mention the miles on the CRV. Most cars and trucks with 4WD have 2 differentials (front and rear) and a transfer case. They all need fluid changes every 3 years or so. Check the Honda owner’s manual for specifics on her CRV.
Once the differential gets noisey it indicates that the gears and/or bearings inside the diff are worn. New fluid may help reduce the wear, but the damage is done. The noise will come back and get louder.
Is it a safety issue? That depends on what parts are wearing out. At some point the diff could fail and just lock up. This locks the rear wheels (in this case) and the car comes to a rapid, hard to control stop. Once it stops thats where it sits, you can’t move the car until someone comes to tow it or push it off the highway. Another type of failure is the insides fall apart under acceleration and no power goes to the wheels, this is less dangerous.
It seems this differential didn’t get proper routine maintenance, and now is showing signs of internal wear.
Thanks for the response. I suspect you are right on the lack of maintenance. Any clue as to whether there is a fix for this? (Can such things be reasonably replaced?) Locking rear wheels does not sound good, and I suspect it will be up to me to do something with the problem. (And I have no clue on the mileage).
Verify they used Honda differential fluid not an equivalent. These Honda rear diff’s are very picky about it. If not change it again and cross your fingers.
No way to diagnose the extent of damage without seeing, hearing, the car and even then you might have to tear it apart to view the gears and see where the wear is occuring. In the meantime follow andrew j’s advice below. A noisey diff can last quite awhile if you can handle the noise. Increased noise, clunking on shifts and when turning are evidence of more wear and that failure possiblity is increasing.
Andrew is correct.
Problems with the center differential are a known issue with CR-Vs of that era, and the solution (no pun intended) is to change the fluid. On this model, the rear differential and the center differential are actually linked, so changing the fluid in the rear diff will also result in a change of the center diff fluid.
However, unless the special, genuine, and expensive [b]Honda Dual-Pump Fluid[/b] is used, the problem will continue. Get the genuine stuff from the Honda parts department, give it to your mechanic, and have him change the fluid again. With any luck, this will resolve the problem.
However, you can’t turn back the clock on bad maintenance, and if the diff fluid was not previously changed (using the correct fluid), it is possible that only replacement of either or both the center and rear differentials will resolve the problem.
Thanks everybody. I’ve checked, and am informed that the real Honda stuff was used.
I want people to realize that it is only certain models and certain manufactures that need differential fluid changes every 30K. This isssue is specific to Honda and the CRV.
Many rear wheel drive vehicles go their entire lifespan with the fluid that came from the factory (incorrectly, but the proof is in the result) and when a change of fluid is done, generic fluid with friction modifiers added (when called for in lmited slip applications) works just fine.
30K is a really short interval when applied to many other vehicles. Follow your manufacture reccommendations on this one. Be espically viligant and espically educated when it comes to vehicles with front,center ,rear differentials.