Differential or Axle noise / clunk?

Hey all - new member from the US here!
Just got a nice 1992 Toyota Paseo 1.5l 5spd, 113,xxx miles

I get a clunk sometimes when shifting gears, after the shift, when changing power, or if I let off the gas when coasting in 4th or 3rd - but not always

I had it up in the air today - checked the usual suspects - suspension, struts, bushings etc.
I noticed 2 new split outer CV boots - so I started checking the axles. Outers are OK still, and no play in-out

With the car in 1st gear, if I turn one wheel, there isn’t any slop per se, although about 3-4 degrees in to the turn, kind of like when the gear engage totally [the other wheel is already moving slightly] there is a clunk from the differential area. No too much of a clunk, but it sure sounds like the sound I am hearing

If I change the direction the wheels are spinning, there is a clunk.
Not much of one, but it’s there EVERY time.

With the car in neutral, if I spin each wheel, I hear the tiniest bit of a sound in the differential area

With the car in 1st, and a friend holding a wheel to keep things from turning - if I try and turn the inner CV, there is about 1mm or less of play in the driver side
The passenger inner CV, however, has a good 5-6mm of play, and makes a clunk type sound.

so my question is: Is this likely to be something like a worn pin or ring gears or something in the differential, or just the inner on the CV joint?

Thanks for any assistance!

-Mark

A ujoint will typically give a clunk when going from reverse to forward, Where is the cunk comeing from, maybe a pm of trans fluid and filter is all that is needed. The minor clunk might be normal, (crossing fingers)

Sounds like you found the culprit. Nice work.
The inner CV joints are designed with a slotted, trifurcated center piece into which the axle slides. It has three bearing assemblies on it, and it slides into an outer housing driven by the transmission. The assembly allows the axle to slide in and out of the slots on the bearings, while also allowing minor articulation, and transfer torque while still letting the axle change length as the steering knuckle turns and the location of the hub relative to the tranny output shaft changes length.

I know, that’s a mouthful. In summary, the inner CV joint’s purpose is to allow the axle to change length while the hub moves up & down with the strut and turns with the steering.

The inner CV joint can wear in a variety of ways, one being wear of the bearings on the three arms, and another being wear of the slots. Either can cause thunking when torsional load is changed.

Great work Here’s a drawing of your Paseo front axle.

A paseo is FWD so no U-joint…
And 5spd, so no filter… I wish it could be that easy LOL

Thank you, sir.
Axles I can handle.
There are literally 0 donor tranmissions for this car at any yards around, so I was fearing Murphy, even after noticing the inner CV rotational play.
Guess I’ll order up a couple axles!

  • edit -
    The lack of play in the length of the axle had me worried that the rotation of the inner CV joint was related to something inside the transmission…

Unlikely.
The axle’s length, or movement along its axis, is not controlled or restrained in any manner by the inner CV joint. As a matter of fact the inner CV joint’s purpose is to allow movement of the axle axially (I think I sprained my tung saying that :open_mouth:) . The CV joint, does, however, secure the wheel to the tranny in its rotating axis. Sounds like that is the force that’s causing the clunking and thus the inner CV joint is the likely suspect.

It doesn’t sound like a transmission problem to me either. You say you have two split boots, so you’ll have to fix that problem anyway. If the boot has been split for any time at all the corresponding CV joint will be damaged and need replacing. Start there before worrying about the transmission (other than checking its fluid level) as it will give you or your shop an opportunity to inspect both half shafts on the bench.

The boots just split in the last 4000 miles or so - but since CV axles are so relatively inexpensive compared to the time required to re-boot, that I was going to change them for some re-man units before winter regardless.
I’m quite familiar with outer CV noise - there is none yet.)
Did a drain/fill of the gear oil about 3000 miles ago - brown with some black swirls(suspended wear particles I suspect). Let out just under a quart the other day for inspection after 3000 miles - gear oil looks brand new.

That was a pretty good description of the wear…modes of the inner CV by the previous poster - but Im afraid it went a bit over my head, at least as far as understanding how the one side can rotate a bit when it shouldn’t, and why/how I am hearing the little clunk come seemingly from inside the diff.

I guess the clunk is transfering through the splined shaft & only seeming to come from inside?

TL;DR
Most important - What should I look for when I remove the axles? Inner CV wise that is.

Thanks everyone!

Many shops would do it that way too. For $$ and cents reasons, like you say. However you do it, suggest you fix the axle problem before trying to diagnose a transmission problem. B/c fixing the axle problem may well resolve the other symptoms.

Toyota’s 5 speed manual transaxles are such robust beasts that we rarely hear of any problems about them here. You probably have the same one I do on my 92 Corolla, the Toyota M5. When we do, like I say very infrequently, it is usually a synchronizer is wearing out and making for a noisy shift experience. I don’t recall ever hearing a complaint here about the differential component of the Toyota manual transaxle. That would be the more likely place you’d get a clunk happening, if it was coming from the transmission. I continue to suspect for your clunk the axles, wheel bearings, brakes, or suspension system.

Good call. I was thinking diff - but with my diagnosis or…checks & the
advice from everyone here - I was going to do the axles first anyway, but
now I’m not so worried about the differential. Broke a diff pin in a honda
back when… borked the whole go system!

Here is another quick question. My first daily driver with a stick was a 92 Tercel with a 4 speed. The entire 50000 miles I drove the car in about 18 months it always seemed like either the clutch was worn or greezy. It just always seem like it would chatter if things were cold and it was just always kind of weird going into 1st or 2nd and having a smooth take off. I never touched the clutch on that car but I bought it with 50,000 miles and sold it with 120 or something.

So my crappy old truck with a hydraulic clutch starts getting traction as soon as I start lifting off on the clutch pedal.

It’s like this car I have to let the clutch out further sometimes it’s just a little funky going into gears not actually shifting more clutch pedal related.
I’m well versed in driving a manual

So this clutch pedal, or feel, or whatnot SUCKS. I don’t notice any slipping when fully in gear. Did a big hill, hit 3rd when I needed 2nd and bogged the motor - no raising of RPM without speed increase

Bled the black clutch fluid.

I’m basically used to the clutch now - but I don’t like it… however since it reminds me so much of my Tercel from years ago I’m having a feeling that maybe this is just the way that the clutch pedal feels on these cars.

Unfortunately currently I can’t think of any succinct way to describe the feel of the pedal and he better than I just did…

Anyone thoughts?

Also - if I dont warm the car up for a bit - 5min or so - it runs great - but say I hit second gear pulling down the block.

Unless I am EVER SO GINGER on the gas, in 2nd clutch fully released, the car wants to go all jerky for a sec - like voom - a - voom - A - voom - a… Motor seems like a top when its doing that, and usually after a few shifts - problem solved…

I am thinking maybe the seal behind the flywheel is letting some oil leak out, which burns or wears off pretty quickly?

But if I warm up until the temp gauge hits the first line - the jerkyness is gone or minimal. And I stop & start & drive ALLLLLL day - after morning, no issues…

Behind the flywheel seal?

Possibly the seal. My impression while reading your post though is that the clutch/flywheel surfaces are a little glazed. And there’s a pretty good chance there’s nothing at all wrong, other than you don’t like the way it feels. I had a cousin years ago who constantly complained about her car’s clutch. Her complaint: It didn’t engage right away as you lifted the pedal, instead it would engage a little higher on the pedal than she preferred. Other friends, mechanics test drove the car and said they could see what she meant, but that it was normal for that make and model of car. Her clutch problem got solved one weekend when she left her car at the airport parking lot while she took a short trip. When she came back her car wouldn’t start, no matter what she tried, wouldn’t even crank. She calls AAA who show up an hour or two later, open the hood, and say “there’s your problem”. Pointing at the empty engine compartment … engine thief was busy at work that day.

The clunking generally comes from the 43401B assembly. the piece with three fingers sticking out of it at 120 degrees each has three bearing assemblies on each one of the fingers. The bearing slides into the shots on the housing. The noise originates due to wear in those parts and travels down the shaft.

I’ve got my new axles on order because that is pretty obviously a definite issue. Once I have them out I’m definitely going to do a little bit of disassembly just to check the wear

Unfortunately I’m having a new and somewhat distressing issue.

Twice now very recently in the last 3 or 4 days I’ve popped out of reverse with a loud clunk when pulling out of a parking space. This is all the more distressing since after the first time it happened I’ve been avoiding using Reverse by allowing gravity to pull me backwards or parking in a spot that I would not need to reverse out of. I’m not super well-versed with the internals of a manual transmission but I do believe that the reverse gear on this car is straight cut and is some sort of different assembly than the regular gears and forks cetera. Perhaps someone could shine a light on this issue

Also I should say I’ve only had this car for four maybe five thousand miles now. I drove the majority of those miles before changing the gear oil. I already describe the condition of the oil when it came out and I believe it was a tiny bit low but not much less than half a quart I would say. I filled the transmission with generic gear oil and I believe the W spec # is 5 weight off too thin? Anyway it’s Oriley Costal dino oil. The only thing in the exact correct weight is $12 a quart.

I think it’s likely that there may be some glazing on the clutch plate and I’m just not a huge fan also of how this clutch engages I’m not going to worry about that at this point

I feel fairly confident that the slightly off weight gear oil is not causing the car to pop out of reverse on occasion I also don’t think the axles or rather the passenger side axle with the excess rotational play would cause that either.

I suppose I can work around the reverse situation for the time being until I’m in a position to have the vehicle down for enough time to pull the transmission off and do some inspection and repair. If I don’t do anything sooner rather than later am i setting myself up for a major issue though?

Thankfully this is a relatively inexpensive car but I don’t have enough money to the point to where it’s not an issue to just let things break if you know what I mean.

While I’m on a bit of a tangent. When I hit certain bumps just right the rear passenger side goes “Sproiiiiingggg!” like a cartoon. Rear strut, huh?

Thanks again all!

Assuming this is a manual, your reverse gear is, in fact, straight cut (33331).
MCL228B

I gotta tell you, using the wrong lubricant in a modern transmission is just about the most risky thing you can do. Your saving of $12/quart may cost you big time. I’d suggest that you drain the tranny and put the correct stuff in ASAP. Hopefully your problems not related to the CV joint will go away. Your symptoms do not sound like clutch issues.

As to the “Sproiiiiingggg!”, the best place to start looking is under the car. Could be a bad damper, a frozen sway bar link, or 1,000 other things.

is 1992 modern? it calls for multipurpose gear oil GL-4 or GL-5 75w-90. the
only 75w-90 around is synthetic which I don’t even think was around in 92.
I’m using 80w-90 GL-5. at temp, its the exact same viscosity… Both times
I popped from reverse, the car wasn’t cold or at temp, mayve 140 degrees or
so - just on the gauge.
Does the correct oil, in temperate climate, with an aprox 8% difference in
the W weight (difference of 5 between 75&80) only really matter? For thick
smelly multipurpose gear oil?
I don’t know - if it weren’t for the timing of the situation I would say
there is no way that could possibly be the cause of the car popping out of
reverse.

and yes - 5spd manual

I’ve got to figure that the new gear oil I put in is orders of magnitude
closer to spec in viscosity not to mention suspended wear particles Etc
then the goop that came out

You can use 75W-90 or 80W-90 in that transmission;

1992 Toyota 5 speed

I figured as much. I’m going to just pay really close attention and make
sure I’m fully engaged in gear when I use reverse cuz there’s a definite
possibility that both of those times I experienced shifter popping out of
reverse I might not have fully had thr gear engaged. I kinda doubt it, but
there’s not much else to do for that right now because I’m certainly not
planning on pulling the transmission when I do those axles!

Thanks for the advice everyone!