[30ONA]

So I have a spare gearbox which I took to get rebuilt to replace the one in my daily. All the oil came out on the highway and damaged the bearings at least. I've been told the input shaft, counter shaft, 5th gear main and 5th gear c/shaft gears all need replacing on the spare box. So I have a few options and a question.
What would cause these parts to be damaged, is it killer do be damaged in my fault too?

Option 1, struggle along with my current box till it dies at some point. Then what
Option 2, take a gamble and pull apart my current box from my daily drive in the hope it has the parts the other box needs or visa versa. My current box was damaged when all the oil dropped out so it whines in all gears except 4. Also no smooth gear changes under 5000 unless really slow changes.
Option 3, buy the parts for 1300 on top of the rebuild cost, total cost for the rebuild would be 3500 plus install.
Option 4, Option 2 but also buy the spare parts and return what is not needed. Forking it the cost of the shipping. So I would get back some of the 1300.

If I could take the car off the road for a month I'd go Option 2 then buy the parts needed but I don't have the luxury of another car.

What are people's thoughts?

[fordem]

First - I find it really hard to fathom how, not one, but two boxes "dropped all the oil out" - seems quite unlikely unless someone loosens the drain plug. What would cause these parts to be damaged? I would have thought that would have been pretty obvious - running with no or low lubricant will damage the gears.

That said, since both boxes suffered a similar failure, it's highly likely that both boxes have similar defective parts - the second box is whining in all gears except fourth, which suggests the input shaft, countershaft and pretty much all the gears will be damaged - fourth gear is a 1:1 so there are no gears driving anything when fourth is selected, just the input shaft coupled directly to the main shaft - the spare box, you haven't mentioned first, second & third gears, so it might be less expensive to fix that one.

Option 1 just postpones the need to make a decision, virtually guaranteeing you'll be stranded at some point
Option 2 is not really an option because you need the use of the vehicle, and both boxes will probably need the same parts
Option 4 is also not an option because both boxes will probably need the same parts.

You're left with option 3

[Gwagensteve]

Option 5- source a second hand J20 manual that hasn’t “dropped all its oil”

[watermouse]

The other option you have is a partial rebuild.
I decided to recon my own j20a gearbox with this https://www.ebay.com/itm/181335825989.
As long as the gears themselves are not chipped or escessively worn then this will certainly extend the life of your gearbox and quieten it down. Most of the noise you describe is the result of the rear countershaft bearing collapsing due to oil starvation/low oil level. The shaft offsets under load (in all gears except 4th) causing poor gear meshing, noise and wear.

If you don't want to or can't do-it-yourself then you would need to negotiate with your gearbox rebuilder to do this without a warranty. At the end of the day a professional doesn't want to see the box back in their workshop with the potential for a warranty fix. Get them to put the bearings and seals in, pay cash, no receipt, no expectations on them.

[Gwagensteve]

I would be reluctant to reuse any gear from a box that failed due to loss of oil.

[sideways]

Gwagensteve wrote:

I would be reluctant to reuse any gear from a box that failed due to loss of oil.

+1

I'd find a good used gearbox and rebuild that. The parts cost of trying to repair a stuffed gearbox will quickly outstrip the cost of a good second hand one.

[30ONA]

Are there any other models that use the same box?

To clarify, I have no history on the box that is stripped apart. The box in my car has done over 20,000k since the oil dropped but has not got worse.

[fordem]

I believe the 1.6 & 2.0 engined second gen Grand Vitara share the same box.

[30ONA]

fordem wrote:

I believe the 1.6 & 2.0 engined second gen Grand Vitara share the same box.

Second gen. So 2005+?
Mine is 04
I looked at the past numbers for the 04 2l and 1.6l box and they are not the same.

[30ONA]

It just dawned on me that I hadn't even confirmed it's the right gearbox. I got it when I bought a j20 motor but it was not bolted up.

It has a number stamped on it 4119242. Does this identify the box?

[30ONA]

So the replacement box clutch and associated parts are in. However I'm not happy with the gear changes. The workshop did not advise to replace the syncro gears. The gear changes are a two motion thing to avoid clunky forced changes. Is this how the box was originally? Should I change the oil? I'm using Penrite 75-90 with two tubes of their shift eze.

I also ordered new shifter bush and locating bush for the stick. In case it is slack in the shifter. It feels like sometimes the shifter box is getting hung up or something. You can't smoothly go from one gear to another in one motion. You need to have a pause to de-load the stick in between. Is this normal? Also reverse can still be finicky on occasion.

[fordem]

You've been driving a J20a GV for what, six years now? Why do you keep asking if it's normal when you know it's not???

[30ONA]

fordem wrote:

You've been driving a J20a GV for what, six years now? Why do you keep asking if it's normal when you know it's not???

Fordem, that's not helpful.

I bought the car with 170,000 so I don't know what it was like when new/normal. It now has 240,000 so as far as I know this is how they all are. I've never driven another one hence why I'm asking here.

The replacement gearbox which was rebuilt with new bearings and seals and installed only 2 weeks ago appears to shift similar to the one I had before, but now no bearing noises. It does shift slightly better but not what I would expect from a rebuild. So I have not been driving this new gearbox for 6 years if that's what you mean. Both gearbox's used the same oil could that be contributing? Is there a better oil for these gearbox's?

[sideways]

So it doesn't crunch between gearshifts, it's just hard to shift? Certainly try a different oil.

[30ONA]

sideways wrote:

So it doesn't crunch between gearshifts, it's just hard to shift? Certainly try a different oil.

It doesn't crunch like when you miss a gear but there is a sort of crunch grind into the gear. Like it doesn't go quietly every time.

Looking at some oils the royal purple and Amsoil synthetics look to be good products. Does anyone have experience with these before I throw another $80 at it?

[30ONA]

Ok so after going back to the gearbox rebuilder twice and my mechanic who installed we all think its a clutch issue. The clutch is not 100% disengaging. For example when you are sitting idle clutch engaged in neutral, then move it to 1st you hear the rear diff engage. Like the gearbox has been spinning the whole time. So when you make changes in other gear the same thing happens. It's either really tight or clunks into gear. Any ideas? All Suzuki parts used except the clutch kit.

Can I put a bore scope in the fork hole to check if the clutch is fully disengaging? Perhaps the throw out bearing is getting stuck?

And then I found this. https://www.clutchindustries.com.au/non ... ur-suzuki/
But the fork is a new suzuki one.

[fordem]

What does clutch engaged mean to you - pedal up or down?

When you depress the pedal, the clutch disengages, when you release the pedal the clutch engages allowing the engine to turn the rest of the drive train - when the clutch is engaged in neutral with the engine idling, roughly two thirds of the gearbox is still rotating, the input shaft, the layshaft, all the gears, except reverse and possibly fifth, are all rotating, the only major part that's not rotating is the output shaft.

If you have the clutch depressed (disengaged), everything should come to a stop, you should not "hear the diff engage", so yes, there is a problem with clutch drag, but that said, clutch drag does not normally cause the synchros to crunch the way you have described it. My guess is you have worn synchromesh rings, and this, by the way, is not based on your statement that "The workshop did not advise to replace the syncro gears", I consider that to be confirmation.

Clutch drag typically shows up as a difficulty in selecting first or reverse from a standstill, it would have to be quite severe to show up with the vehicle in motion.

The purpose of the syncho rings is to make shifting easier, without them, the driver would have to "rev match" the rotating gears to engage them without grinding or crunching, the synchro rings are there to do that, as the hubs slide, friction between tapered surfaces allows the two parts (one gear and one engagement hub) that are rotating at different speeds, to come to the same speed and slip in without a crunch.

In short, the mechanism is designed specifically to allow the two parts, rotating at different speeds to come together at one speed, and as a general rule, it works very well unless you, the driver, are doing something you shouldn't, like trying to downshift into a lower gear at an excessively high road speed, say from fifth at 100km/h to second, it will (or should) let you do fourth to second at 20~30km/h without a peep.

The reason that clutch drag is most noticed in first or reverse is that the vehicle is at a standstill, and you're not dealing with two rotating items, one of them is stationary - so yes, whilst the fact that you can "hear the diff engage" suggests the clutch is not disengaging fully, the fact that you can get a crunch at every shift suggests the synchro rings are worn.

I doubt a bore scope through the clutch fork hole is going to show you anything, other than the outside of the clutch, you might be able to see the throw out bearing moving, but I doubt that will reveal anything of value.

[30ONA]

Your description of clutch drag is exactly what happens. But why would I get this with all new parts? It seemed to drive home ok without jamming up once. But parked in the driveway all the symptoms you describe of clutch drag. I've move the pedal all the way up and the master cylinder right out and it still did it. I've returned it to normal. I googled the issue on the clutch website clutch industries and they refer to a cracked fork being the cause. But it's brand new from suzuki. Could there be a linkage issue in the clutch and fork arrangement?
Where im stuck now is what next because I don't want to pay hundreds more removing it to do what? Replace the clutch again? This is also my daily.

fordem wrote:

What does clutch engaged mean to you - pedal up or down?

When you depress the pedal, the clutch disengages, when you release the pedal the clutch engages allowing the engine to turn the rest of the drive train - when the clutch is engaged in neutral with the engine idling, roughly two thirds of the gearbox is still rotating, the input shaft, the layshaft, all the gears, except reverse and possibly fifth, are all rotating, the only major part that's not rotating is the output shaft.

If you have the clutch depressed (disengaged), everything should come to a stop, you should not "hear the diff engage", so yes, there is a problem with clutch drag, but that said, clutch drag does not normally cause the synchros to crunch the way you have described it. My guess is you have worn synchromesh rings, and this, by the way, is not based on your statement that "The workshop did not advise to replace the syncro gears", I consider that to be confirmation.

Clutch drag typically shows up as a difficulty in selecting first or reverse from a standstill, it would have to be quite severe to show up with the vehicle in motion.

The purpose of the syncho rings is to make shifting easier, without them, the driver would have to "rev match" the rotating gears to engage them without grinding or crunching, the synchro rings are there to do that, as the hubs slide, friction between tapered surfaces allows the two parts (one gear and one engagement hub) that are rotating at different speeds, to come to the same speed and slip in without a crunch.

In short, the mechanism is designed specifically to allow the two parts, rotating at different speeds to come together at one speed, and as a general rule, it works very well unless you, the driver, are doing something you shouldn't, like trying to downshift into a lower gear at an excessively high road speed, say from fifth at 100km/h to second, it will (or should) let you do fourth to second at 20~30km/h without a peep.

The reason that clutch drag is most noticed in first or reverse is that the vehicle is at a standstill, and you're not dealing with two rotating items, one of them is stationary - so yes, whilst the fact that you can "hear the diff engage" suggests the clutch is not disengaging fully, the fact that you can get a crunch at every shift suggests the synchro rings are worn.

I doubt a bore scope through the clutch fork hole is going to show you anything, other than the outside of the clutch, you might be able to see the throw out bearing moving, but I doubt that will reveal anything of value.

[sideways]

30ONA wrote:

Your description of clutch drag is exactly what happens. But why would I get this with all new parts?

Bad/seized spigot bearing.
Plate stuck on the splines. Burred over male spline, rough/loose/tight female spline.
New parts that don't work. Sometimes shit happens and the genuine new parts are shit. If genuine parts were perfect there would never be a warranty claim. Also often what comes new in the vehicle is a different part to what is sold by the parts department. I've replaced 2 clutches that drag like yours for seemingly no reason, both were PBR and looked to have nothing wrong with them.
Not enough clutch travel. Incorrect master/slave. Not bled correctly. Master leaking down.
Geometry wrong. Short thrust/thrust holder, thrust holder twisted out of place, bent fork, wrong pushrod ect
Flywheel machined wrong. It's important to maintain the factory step height between the friction surface and where the pressure plate mounts. A while back I did the clutch on a Kioti/DaeDong tractor that previously had a few clutch failures and they'd taken a ton off the flywheel. After that it came to me with the same symptoms as yours, clutch drags/can't shift. I sourced a new flywheel which fixed it. FWIW that tractor was at 3500 hours and with 5 clutch replacements, Kioti might not make the best clutches.

[fordem]

30ONA wrote:

Your description of clutch drag is exactly what happens. But why would I get this with all new parts? It seemed to drive home ok without jamming up once. But parked in the driveway all the symptoms you describe of clutch drag. I've move the pedal all the way up and the master cylinder right out and it still did it. I've returned it to normal. I googled the issue on the clutch website clutch industries and they refer to a cracked fork being the cause. But it's brand new from suzuki. Could there be a linkage issue in the clutch and fork arrangement?
Where im stuck now is what next because I don't want to pay hundreds more removing it to do what? Replace the clutch again? This is also my daily.

First - I suggest you get hold of the FSM and return the adjustments to the factory settings - unless you feel you know better than the design engineers, in which case, you also know better than I do - assuming the right parts have been fitted, there should be no need to deviate from factory recommendations.

Second - what do YOU mean by "all new parts" List what was replaced (as related to the clutch).

Moving on - there are different reasons for clutch drag - anything that prevents the clutch release mechanism from reaching it's full travel will allow the clutch to drag, assuming you've already investigated & dealt with those and the pressure plate is releasing fully, contaminated linings can cause the clutch plate to stick to either the flywheel or pressure plate, a worn or bent input shaft can cause the clutch plate to bind (not slide freely on the input shaft) so that it rubs on either the flywheel or the pressure plate, the condition of the flywheel surface can "trap" the clutch plate (was the flywheel resurfaced), and a defective pilot shaft bearing can cause the input shaft to rotate with the flywheel even though the clutch itself has released and is not dragging.

[30ONA]

fordem wrote:

30ONA wrote:

Your description of clutch drag is exactly what happens. But why would I get this with all new parts? It seemed to drive home ok without jamming up once. But parked in the driveway all the symptoms you describe of clutch drag. I've move the pedal all the way up and the master cylinder right out and it still did it. I've returned it to normal. I googled the issue on the clutch website clutch industries and they refer to a cracked fork being the cause. But it's brand new from suzuki. Could there be a linkage issue in the clutch and fork arrangement?
Where im stuck now is what next because I don't want to pay hundreds more removing it to do what? Replace the clutch again? This is also my daily.

First - I suggest you get hold of the FSM and return the adjustments to the factory settings - unless you feel you know better than the design engineers, in which case, you also know better than I do - assuming the right parts have been fitted, there should be no need to deviate from factory recommendations.

Second - what do YOU mean by "all new parts" List what was replaced (as related to the clutch).

Moving on - there are different reasons for clutch drag - anything that prevents the clutch release mechanism from reaching it's full travel will allow the clutch to drag, assuming you've already investigated & dealt with those and the pressure plate is releasing fully, contaminated linings can cause the clutch plate to stick to either the flywheel or pressure plate, a worn or bent input shaft can cause the clutch plate to bind (not slide freely on the input shaft) so that it rubs on either the flywheel or the pressure plate, the condition of the flywheel surface can "trap" the clutch plate (was the flywheel resurfaced), and a defective pilot shaft bearing can cause the input shaft to rotate with the flywheel even though the clutch itself has released and is not dragging.

I have reset the clutch to FSM.
Gearbox
Rebuilt with new bearings and three parts internally related to 5th gear and the input shaft. These were all suzuki parts. I don't know what bearings were used.
Bell housing
Suzuki fork and pivot ball new
Clutch
Clutch industries kit with release bearing clutch and pressure plate
Back of engine
New rear main suzuki new
New pilot bearing suzuki new
Flywheel machined by mechanics associate. I don't know to what specific so this could be worth investigating if it's a possible cause?

[Gwagensteve]

Bled the clutch hydraulic system/flushed fluid?
Replaced master or slave cylinder?

[30ONA]

Gwagensteve wrote:

Bled the clutch hydraulic system/flushed fluid?
Replaced master or slave cylinder?

Going to bleed again from the top.

Can anyone tell me how much stroke I should be able to measure at the slave? So i can eliminate hydraulic issues?

Perhaps there has been air in the line for ages but the new pressure plate is compressinh the air more than the old one did.

[Gwagensteve]

You never mentioned bleeding or replacing the fluid. Normally the clutch slave cylinder is just unbolted and moved out the way when the gearbox is removed. Is that what you did? Has the fluid been changed? Did it ever drop all the hydraulic fluid? (Ie did you bench bleed the master? Is the fluid to spec? Does the crunching get worse on longer drives?

[30ONA]

Gwagensteve wrote:

You never mentioned bleeding or replacing the fluid. Normally the clutch slave cylinder is just unbolted and moved out the way when the gearbox is removed. Is that what you did? Has the fluid been changed? Did it ever drop all the hydraulic fluid? (Ie did you bench bleed the master? Is the fluid to spec? Does the crunching get worse on longer drives?

The slave was just moved to the side. After having the issue I gravity bleed the line with new dot3 but it did not improve.
It's not crunching like a missed gear and if anything it improves slightly on a longer drive. But that might just be me adapting to it

[fordem]

30ONA wrote:

The slave was just moved to the side. After having the issue I gravity bleed the line with new dot3 but it did not improve.
It's not crunching like a missed gear and if anything it improves slightly on a longer drive. But that might just be me adapting to it

I'm just going to allow these two "quotes" to show the contradiction in your statements...

30ONA wrote:

So the replacement box clutch and associated parts are in. However I'm not happy with the gear changes. The workshop did not advise to replace the syncro gears. The gear changes are a two motion thing to avoid clunky forced changes. Is this how the box was originally? Should I change the oil? I'm using Penrite 75-90 with two tubes of their shift eze.

I also ordered new shifter bush and locating bush for the stick. In case it is slack in the shifter. It feels like sometimes the shifter box is getting hung up or something. You can't smoothly go from one gear to another in one motion. You need to have a pause to de-load the stick in between. Is this normal? Also reverse can still be finicky on occasion.

Maybe the situation has changed, maybe it hasn't, but if it has, you haven't told us.

In my experience (and I daily drive a manual transmission SQ420), the box does not like to be "hustled", but a "two motion thing to avoid clunky forced changes" is definitely NOT normal. It can be shifted in one motion without a "pause to de-load the stick", just don't try to drive it as if it's a "hot hatch" and it will shift like a hot knife through butter, quiet, smooth & effortless.

I've had drivers who are not familiar with my vehicle behind the wheel and they have had no difficulty shifting, one of those people asked to drive it because they hadn't driven a manual transmission vehicle in years.

What you're describing in that second quote IS a synchromesh problem, and the fact that you told us that " the workshop did not advise to replace the syncro gears", suggests that you recognize that.

[30ONA]

Let's start again.
Car running.
Put the car in 1st and you can hear the rear diff before lifting your foot off the clutch.
Drive off and go for second, comes out of 1st but then stops before engaging 2nd. If you wait 1 or 2 seconds you can select 2nd. If you force it, it goes into gear with a thud. Third and sometimes 4th are the same but 3rd not as bad as 2nd and 4th not a bad as 3rd.
Down shifting is fine all the time.
Reverse is reverse. Sometimes fine sometimes clutch in and out to get it.
Big reputable gearbox company have test driven twice with two of their mechanics and claim its not the syncros.
Because they didn't fit the gearbox if I get them to pull it out and is the installation causing the issue I'm up for$$$ and would need to somehow get money back from the guy who installed.

[fordem]

30ONA wrote:

Let's start again.
Car running.
Put the car in 1st and you can hear the rear diff before lifting your foot off the clutch.

Question - how do you know what you're hearing is the rear diff? Do you feel the car move when you shift into first. If the noise is in fact the rear differential, there is a high probability that the clutch is not disengaging fully.

Quote:

Drive off and go for second, comes out of 1st but then stops before engaging 2nd. If you wait 1 or 2 seconds you can select 2nd. If you force it, it goes into gear with a thud. Third and sometimes 4th are the same but 3rd not as bad as 2nd and 4th not a bad as 3rd.

Question - what is there that is likely to prevent the selector hub from sliding in to mesh only for a few seconds? Answer - the synchro rings. Question - why does the selector hub slip into mesh smoothly after a few seconds? Answer - because the relative speeds of the selector hub and the gear have synchronized.

https://youtu.be/e-Lk3FXHubw

Here's a short youtube video showing how the synchronizer mechanism works - the transmission on an SQ420 uses the first style of synchronizer ring shown - there is almost literally nothing in that transmission that can prevent the selector hub from sliding into mesh other than the synchronizer rings.

Quote:

Big reputable gearbox company have test driven twice with two of their mechanics and claim its not the syncros.
Because they didn't fit the gearbox if I get them to pull it out and is the installation causing the issue I'm up for$$$ and would need to somehow get money back from the guy who installed.

For the sake of discussion, let's say they pull it out and it is the synchros, is it going to be fixed for free? Anyway you twist and turn this, you're going to be spending money to get this sorted , and you're going to need to somehow get it back from the guy who did the work previously.

[Gwagensteve]

Chock the car and jack up the drivers side rear wheel. Take the handbrake off. Start the engine with the car in neutral. Depress the clutch and put the gearbox in 1st gear. Keep the clutch depressed. Watch the wheel in your mirror. If the wheel turns, the clutch is not fully disengaging.

And you have shot syncros.

[fordem]

https://youtu.be/0Bqs-oHBBQk

Another youtube video on blocker ring sychronizers