It's not the differential! It's not the brakes!

1999 Honda CR/V, 130K

The stock answer for grinding from the rear of a CR/V is the differential. Mechanic has replaced it twice…one had 90K on it, the other 30K. Of course, also changed diffie fluid to specs. But no relief.

“rrrrrruh” when depressing clutch pedal. Not necessarily metallic sounding.

“AARRRRRRRRRRRRrrrrrrruuuuhhhhh” when braking going downhill or under stress. Low pitch, but medium-loud. Quits when car stops or brake released. Near the end of the noise, it definitely sounds like something rotating that’s slowing down.

[Had brakes checked first…by two mechanics independent of each other, one a brake specialist. Not the brakes.]

Both sounds only start up after car has been driven a bit…first no problems in the first 10 miles, now problems most of the time.

My mechanic took it to Honda today, who said “differential.” //Right.// The mechanic refunded everything we paid and is at a loss.

Does the car make the noise when it is stopped and the clutch pedal is depressed? if the hand brake is the only braking system used (in a testing fashion)do you still get this noise.

A bit unclear about the first paragraph. Are you saying that two used diffs were installed and neither changed the noise parameters at all? what diff is in the car now? (I assume one of the used ones).

We must get the symptons and the remedies attempted in a type of order that conclusions can be drawn from, and this is not happening here, yet.

Thank you for responding, oldschool!!!

  1. No noise when car is stopped & clutch pedal is depressed.
  2. Have not tested with hand-braking only when moving. Will post tonight.
  3. This is a one-owner car with 140K. Two used diffs were installed this fall. First had 90K on it, and did not fix noises, plus added a bad whine at high speeds. Second (still installed) has 30K on it and whine from 2nd diff is gone, but clutch & brake noises have gotten progressively worse = more often, at lower speeds, when clutching between 2nd & 3rd (as well as 3rd to 4th and 4th to 5th), occuring sooner after starting to drive, & sooner/louder/longer when braking.

I suggest you crawl under the CRV and watch if anything is moving that should not be moving when the clutch is pressed. I recently saw a picture of a Honda with shifting issues and the cause was the block was broken allowing the engine and trans to seperate upon application of the clutch.

So we are talking about an odd noise that shows itself during shifts. Let me look.

I have read through this post and I have a couple of questions not asked:

  1. Has anyone checked the drive shaft and u-joints to the rear axle?
  2. Does it do it in 4WD?
  3. checked the transmission itself?
  1. I’ll ask the mechanic tomorrow about the drive shaft & u-joints, and I’ll reply quite late in the day, I’m afraid…
  2. It’s an AWD car…there’s no specific 4WD.
  3. It’s a manual, not an automatic… I am so sorry–I’m fairly auto illiterate. Again, I’ll ask the mechanic tomorrow.

New data just in from the spousal unit:
The mechanic disconnected the drive shaft and drove the car using FWD only == no noises; therefore they eliminated the transmission and the clutch as suspects and focussed on the differential.

Just to be clear, there’s no “issue” clutching and shifting…it all feels & responds fine…just the rrrruuh noise on depressing the clutch. Same with braking…no problem, just the grumble-growl noise when braking under stress (i.e., braking quickly–like when someone cuts in front of you, braking going downhill, or braking to slow down from say 40+ mph–though less and less “stress” is required to get the noise).

So it is the diff,one more time.If it is the differential again what type of repair will you go for,another used part or a rebuilt diff? perhaps a used one that comes with a warranty.

Both diffs the mechanic tried came with his warranty, and he made good. He won’t put in another used one. The Honda dealer (that the mechanic took the car to as a last-ditch effort) is now preparing a quote to put in a “new” one. Don’t know yet if Honda will warranty it.

Yes, the mechanic inspected carefully the drive shaft & u-joings when he disconnected the drive shaft.

Please also see “NEW SOUND” above.

I took the car on my busy day with 25 miles of stop-and-go in hilly Portland.

  1. YES I can get the clutch to squawk a little when clutching at a full stop, especially if the car rolls, like into a pothole. Not always.
  2. NOW I can get the rrruhh from 1st to 2nd gear. It’s quieter, and not always.
  3. NEW SOUND (once) starting out from dead stop in 1st gear (at a stoplight) and going uphill…the back end HOWLED like “WHEOOOP” --the sound of a short blast on a slide whistle. [Gosh, maybe it is the differential??? Third time’s a charm!!!}
  4. Once the braking growl starts on any one trip, then it’s there for the rest of that trip. If I can brake normally, I can go a whole trip without it.

Got the quote from Honda. $2400 for parts and labor for a whole diff. $900 for the back half “including ring and pinion.” This came thru email and it doesn’t say whether it’s new nor whether it’s guaranteed…will have to find out.

$2400 for a “new” differential (“front and back”) built from new parts. 1 year warranty.

it WAS the differential.

Wild guess here but somebody might want to check the engine mounts. Driveshafts can be ruined when they have to negotiate severe angles. The clutch noise makes me guess the same thing.

With engine off, put the car in fourth gear and rock the car back and forth while looking at the engine. See what happens. Hear what happens.