2000 Honda with what sounds like a bad CV JOINT, but Cant be---

I am original owner of a 2000 CRV, it’s in really good shape and has been maintained by me on about 99% of all repairs it has 140k total. I have this thumping noise coming through the floorboard by my feet, under moderate acceleration and it goes away at just about any speed when you quit accelerating. Sounded like a bad halfshaft, I had already replaced one so I did the other side, got worse. So I replaced the one that had been in for just 2 years–no better. Asked the auto parts store for a recommendation and went to that shop, they balanced the tires, checked rotors and concluded I was buying junky rebuild half shafts. I had them replace the one they thought was bad with another rebuild, just as bad or worse…I took home and put in both sides with new halfshafts, I also noticed some play in jackshaft bearing and replaced that as well…no better. Shop claims that a website they subscribe to says that 50% of aftermarket halfshafts for CRV are no good. But honestly we are 5 for 5 bad, last two were new from NAPA. Pulled things apart and checked wheel bearings left side was sticky so had machine shop press one into the knuckle, right side was done about 14 months ago. Also disconnected drive line and drove it as a 2 wheel drive vehicle…no better. Running out of ideas, would a broken tire belt only make noise on acceleration or after a corner when you accelerate? Is this a possible indication of my transaxle going out? — sign me Naked and Screaming in Wisconsin

I think you’ve pretty much exhausted that it’s a CV-joint problem.

But you might want to look at the cross support and the cross support stiffener.

The cross support attaches to the uni-body on one side by three bolts right under the floorboard. And since the cross support is what supports the lower suspension, if the support/bolts are worn, it can cause a noise when turning and accelerating.

Tester

With a unitized body, it is possible for noises to be…transmitted…in such a way that they sound like they are coming from a different location then where they really originate.

So…I would suggest checking the motor mounts and the transmission mounts. Even though the CRV isn’t one of the Honda models known for mount problems, it is entirely possible that there is a broken motor mount and/or trans mount.

Is it FWD or AWD?

texases: AWD

Quote from OP: “Also disconnected drive line and drove it as a 2 wheel drive vehicle”

b

Thanks, missed that.

Noises that go away on coasting like that are usually in the driveline somewhere or another, usually it would be a half-shaft and in this symptom I’d expect the tri-pod part of the halfshaft.

But you’ve pretty much eliminated the half shaft … so about the only thing that is left is the output part of the transmission. Probably something amiss is the differential. Actually years ago I had a rear wheel drive car make this same kind of thumping nose, really loud, and that was the rear differential on the fritz.

Edit: Have you checked the transaxle fluid level?

Has this car ever been wrecked, or even hit any really big bumps?

I am going to agree with what was said above about it being in the trans or diff. You might want to have it looked at a shop where it can be driven on a rack in the air, so the tech can pinpoint the noise. One other thing you could do is drain the trans and diff and look for metal or other debris in the fluid.

Control arm and/or ball joint problem?
I vaguely remember a service bulletin or Recall about control arm issues on CR-Vs and at 15 years of age it’s certainly possible.

An issue in that area could certainly cause a thunk in the floor.

As a footnote and if you want to check reman halfshafts at the parts store before taking them home and discovering they’re on shaky ground you might do this.
Grasp the shaft in one hand and slowly move the joint through its range of motion.
The joint should not be sloppy and you should feel a smooth range of movement in all directions.

If you feel a “hitch” in it so to speak then odds are the reman is a shaft that went through the cleaning process and was thrown together without actually being remanned.
Cleaning, new paint, and new boots make it look good though.

Thanks to all for the responses, some good ideas here that i haven’t followed out on. Answering some of your questions, I have replaced the upper and lower arms,ball joints, sway bar links and struts in the last two years so front end should be pretty tight. I am the original owner and no accidents in its history. Transaxle fluid looks great, smells normal very little metal on the plug/magnet. I will check the differential gear oil, motor mounts, cross members, bolts and frame. i have already replaced a few parts in the frame that have rusted out, Wisconsin salt. I put it up on my in laws rack and ran it saw nothing, also shop that I took it to for diagnosis tried it as well and only felt the halfshaft was bad. I will pull halfshafts and try your testing method, have some of the short term replacements still here so can try them out as well. Does make me think the motor mounts could be the ticket with me not seeing anything while on the rack, no load on wheels motor shouldn’t rock should it?

Make sure both half shafts are the right length. There’s been reports here of people getting rebuilt half shafts having the wrong dimensions.

I would avoid brand new Chinese axleshaft. I’ve had almost nothing but trouble with those

In most cases, I would prefer a quality remanned axleshaft over Chinese new

I believe EMPI axleshafts are pretty good. Or at least, they used to be

A friend bought reman half shaft that were the wrong length. The problem was he turned in the half shaft for the core fee. Then he had to prove to himself and the store they were wrong.

Inner tulip joints will thump on acceleration and can be tough to diagnose. I have found that the rebuilts that fail out of the box have shims that fit into the slots and the slots are supposed to be machined until they are straight but they often cut to some oversize spec leaving a gap and install the shim over the gap. The new parts that failed were all Chinese and one of the tulip slots was machined over sized on some. I totally stopped buying the new Chinese axles.

As for the unibody, I have seen a few cars with deteriorated rubber cushions at the sub-frame to floor attachment. Those cars would thump on moderate acceleration or braking expecially while in a turn. The faulty cushion on several Ford Tauruses was a 1/4" thick disc about 6 inches in diameter with a 1 inch centered hole. Ford did not offer that cushion as a replacement part and I manufacured them from industrial conveyor belt material and never had a complaint. The cars were in commercial use and took quite a beating I guess. But I am not familiar with the sub frame on a CRX.

And I found the sub frame problem by putting junk rims under each tire and with the car resting that high I rolled under it and had a man hold the brake and repeatedly torque the engine up to load the drive train. Doing so made the loose joint obvious. I was surprised that the alignment wasn’t out of spec due to the looseness.

I believe that some aftermarket halfshafts also fail for this reason. Some facilities regrind the bearing surface inside the joint and install oversized balls a few thousandths bigger. It would be similar to grinding crankshaft journals and using oversized bearings.

The problem is that the bearing surface is hardened steel and after the regrind they do not treat the steel to reharden it. This ends up with hardened steel balls moving around on a non-hardened surface and then quite often the wear comes on much more quickly.

I don’t know if the place is still around or not but there is or was a small axle shaft company in Midwest City, OK that did nothing but replace halfshafts on cars. They had a huge assortment of boots, clamps, various oversizes of balls by the countless thousands, and so on along with a machine to grind the bearing races.
I had stopped in there one time to pick up some oddball boots and during a conversation I heard the pitch about being able to handle anything that came in the door including the regrinding.

When I asked about what that does to the hardened surfaces the only thing I heard was a little stammering and quickly veering off the question.