MrMazda92 wrote:Does the car feel almost like it's bouncing up and down when you drive? Less of a "bounce" and more of a vibration as you reach freeway speeds?
No, the vibration felt inside (hehe ) is actually very subtle. As I've said, it's much more noise than vibration, but you only need to look at the rearview mirror at 30 - 40 MPH and the image is "brrrrrrr"
MrMazda92 wrote:Does the car feel almost like it's bouncing up and down when you drive? Less of a "bounce" and more of a vibration as you reach freeway speeds?
No, the vibration felt inside (hehe ) is actually very subtle. As I've said, it's much more noise than vibration, but you only need to look at the rearview mirror at 30 - 40 MPH and the image is "brrrrrrr"
Have you tried swapping the wheels from the front to the back?
1993 Mazda Mx-3 GS-Sold 1992 GS "The Bucket" Gone. 1993 GS 2.5 KLDE. Current daily.
92 GS 5spd for sale! Sold it....after I got a hatch cover in great condition 92 GS Auction Car, most expensive non-running mx-3 I have ever bought... Parted out and Crushed.
Have you put a stethoscope up to the transmission and isolated the source of the sound to the transmission? Many of the other symptoms you describe could be wheel bearings. If those are already replaced - I did not see that in the last several posts.
I think you've mostly replaced worn out parts so far, but tearing a transmission apart deserves some reasonable confirmation that it is necessary.
I didn't actually see the part # for the bearing you used to replace the intermediate shaft support bearing. In my defense it is fairly common to use carrier or support bearing as terms to describe a bearing that is used to support a drive shaft.
Ok, I am kind of growing tired of repeating this: IT IS NOT THE WHEEL BEARINGS.
With the car on jackstands, the wheel hubs disassembled, the engine running and the car in any gear, the sound is intensified exponentially, since no weight is on the axles. I have done several "rock back and forth" tests of both wheels, and the both are SOLID. No play whatsoever. Sorry to sound like a douche, but I've stated several times in the thread that the wheel bearings have been eliminated as a potential suspect.
Also, the sound was distinctively coming from where the driver's side CV axle enters the transmission. This is why, before discovering the bad ISB, I suspected either bad carrier bearings or misaligned diff gears, which still seem to be the most likely suspects.
As far was swapping tires, this would be pointless - the sound is still present without the wheels on the car, so tires/bent wheels is not the answer.
Before anyone makes any suggestions, please read atleast from page 9 or 10 onward, so I don't have to explain this over and over.
I appreciate everyone's input, but I do feel that we're beating around the bush here; there are no other drivetrain components that could cause this kind of vibration. However, I am still open for suggestions, as long as it's not:
CV Axles
Intermediate Shaft Bearing
Wheel bearings
Brake rotors
Brake pads
Brake fluid
Tires (including out-of-balance. I recently had them re-balanced)
Wheels
Transmission (the vibration is not present when at a stop and in neutral - only when the car is MOVING)
Loose lug nuts
Transmission fluid (just put in new fluid)
I said it before, but I'll say it again... a used tranny would have been cheaper. Maybe not cheaper than a few individual parts, but the time and money invested in trouble-shooting would have gotten you back on the road(so to speak) already...
I'm all for DIY repairs, especially for the experience of learning, but this is starting to look like my own nightmare. Seriously, if it's internal and money is an issue, replace the damn thing... That's my .10 cents you guys, sucky as it may be to hear it.
I've studied the disassembly and reassembly of a MX transmission, and it isn't that hard at all. Average enthusiast do it often when swapping to a LSD diff.
I understand your belief that replacing the transmission would seem less labor intensive, but honestly, if the diff bearings just need to be replaced, and you're already as far as having the trans pulled out, you may as well just tear down and replace them. Once the trans is out, you can move indoors for the actual tear down. It can be torn down and the diff removed in a few hours. Then it's just a matter of getting the old bearings pressed off and new ones pressed on. Reassemble and reinstall.
I can kind of see the mentality of just replacing the trans to begin with, but that's a bit presumptuous to me; A transmission problem would have indicated one or both of two symptoms:
- Difficulty engaging gears and/or "popping" out of gear
- Violent vibration, knocking or whirring even when sitting still and the transmission in neutral. (The input/counter shafts still spin when in neutral)
Since I had neither of these, it was reasonable to deduce that the transmission itself was not the issue. Therefore, replacing it would seem a bit like overkill, since the original is in perfect working order. Also, I had no "wandering," "pulling to one side" or "shimmy" in the steering wheel, so that eliminates the tires, wheels, brakes, wheel bearings, or any other steering components.
From there, it is logical to conclude that the sound must be coming from the drivetrain, excluding the transmission itself.
With both CV axles replaced, and the bad ISB replaced, there is no other drivetrain component left EXCEPT the differential.
As I said, either one or both carrier (differential) bearings are bad, or when the numbskulls that did the engine swap pulled the old axles, they did not insert plugs into the holes to hold the diff gears in place, causing them to get misaligned.
In either case, it's an easy fix, and not worth scavenging the junkyards for a replacement tranny when brand new bearings are only 3 blocks away.
Nd4SpdSe wrote:Have you figured out if it's the drivers or passenger side?
My best friend had a vibration with his old *gulp* Optra, it was an actual bend axle that was causing it.
The sound seems to be coming from the driver's side, right where the axle enters the transmission. The axle is brand new.
Obviously, if one diff bearing is bad, you should never replace the one; always replace both diff bearings.
I tore down and rebuilt the rear end in my SN95 a few months ago to install 3.73 gears and an LSD, so I've had some hands on dealing with differentials.
On the Mazdas, once the two internal shafts are removed from the transmission, the differential assembly can be lifted out. The carrier (differential) is almost identical in design to those of RWD cars.
I don't know how mechanically inclined some of you are, but I posted a link few pages ago in this thread to another forum where a guy does a tear down and rebuild of the MX-3 manual transmission to install a LSD diff. Lots of pics, so it's easy to follow.
I guess my mechanic did a trick with the car on the hoist was to clamp the brake on one side and allow the other side to spin, help isolate the vibration. I think it really depends on the type of vibration.
1992 Mazda Mx-3 GSR - 2.5L KLZE : Award Winning Show Car & Race Car ['02-'09] (Retired) 2004 Mazda RX-8 GT - Renesis Wankel : LS3 Coils, BHR Mid-Pipe + Falken RT-615K 245/40r18 2011 Mazda Mazda2 GS - 1.5L Manual : Yozora Edition (1 of 500) 2003 Nissan Xterra SE - 4x4 Supercharged : 2" Body Lift, 4" Suspension Lift & 33" MTR Kevlar 2001 Nissan Frontier SE - The Frontrailer : Expedition/Off-Road Trailer Project
Thought I'd post an update after a day of wrenching on it.
Once again, we've temporarily waited on pulling the transmission, because.....and I may have to eat my words here.....we think the driver's side wheel bearing is bad.
Rotating the hub, I noticed mild resistance with a faint "dragging" sound. So we went about removing the knuckle & hub. The hub is out, and all of the bearings are intact, and don't appear damaged, so I'm naturally still very skeptical. My money is still on the diff, but until we get the old bearings pressed out and new ones pressed in tomorrow, we're going to wait on the transmission.
The wheel bearings may have been slightly worn, but I don't think it's enough to cause the kind of noise it's been making.
Anywho, I'll post again when we're reassembled and road tested.
It's been said that hubs can "eat" wheel bearings, so to speak... I am not sure how or why, but I do remember seeing mention of it on here. I believe it was wytbishop that said it, but I could be wrong... In general, I take what he says at face value. I have yet to see him share information that he can't personally attest to the accuracy of, unlike me.
I am perfectly happy quoting others, and throwing up links... but it has gotten me in "trouble" in the past, as far as accuracy goes.
Well, we reinstalled the spindle tonight and everything is great. Finally.
The wheel bearing was indeed the problem, but the ball bearings themselves were not the issue; the outer races had developed impressions of the bearings in them, causing a very bumpy ride for the ball bearings. This kind of fault cannot be detected using the "rock the wheel" method, which is why I had dismissed the wheel bearings. Anywho, a few small things to tidy up and she's perfect:
Replace gasket for power steering hose-to-pump flange.
Fix minor leak in top of radiator.
Replace shift linkage bushings
Replace IAC valve.
Thanks for all your help guys, and I apologize for being an a-- when everyone kept suggesting wheel bearings.
) is actually very subtle. As I've said, it's much more noise than vibration, but you only need to look at the rearview mirror at 30 - 40 MPH and the image is "brrrrrrr"
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