Piazza gearbox

Post by **Piazza_man** » Thu May 24, 2012 8:33 pm

Bugger me. If its not one thing it's another. This time it's the gearbox and it turns out a lack of oil at some stage had almost destroyed the box. I can count on one hand how many times I drove the car since taking ownership several months ago, so I know it wasn't me. It was apparently a ticking time-bomb.

I'm told I'll need another input and cluster gear if I can't find another box. I might have more success finding replacement parts than a box at this stage so that's what I'm concentrating on right now.

Elky tells me the input and main shafts off a Shuttle or a Rodeo 2.3L 2wd box should be direct swap. Is this right guys? I also hear the Gemini input shaft is different so not a direct swap, although it can be done.The Gemini box will be a last resort but would anyone recommend anything else here? Would anyone have these shafts lying around. I'm not going to even bother about asking for another box.

Bugle · Post by **Bugle** » Thu May 24, 2012 9:18 pm

There's no way you'll find shafts outside a gearbox unless you're ordering them from Isuzu..
According to this some KB 4ZD1 Rodeos have the same ratios except for 5th
http://www.isuzupiazza.com/forum/viewtopic.php?t=688
But then below that other KB 4ZD1 Rodeos have completely different ratios? Check the ratios before you hand over the cash for one..

MUA is good if you have the skills to make a completely new remote shifter for it to suit the Piazza

Post by **Piazza_man** » Thu May 24, 2012 11:15 pm

I wonder if Rodeobob has any more stuff at his place. I might send him a PM. My mechanic will be trying to locate a KB 4ZD1 or Shuttle box in the meantime, but if I found a box wouldn't I just need to take the shafts out and replace them in my original box, if the rest of my box is OK? That way I keep my ratios.

Bugle · Post by **Bugle** » Fri May 25, 2012 1:38 pm

The shafts and gears are machined as one piece so you can't change ratios. Don't bother with a shuttle box the ratios are crap, would be better off with a Gemini gearbox.

Post by **Piazza_man** » Fri May 25, 2012 4:16 pm

Oh OK. Goes to show you what I know about gearboxes. What would the ratios on the Rodeo box like, because I just got word the gearbox mechanic located a 4zd1 box and is bringing it in to check its compatability.

Bugle · Post by **Bugle** » Fri May 25, 2012 6:12 pm

Of the 2 ratio sets for the 4ZD1 box that Rodeobob listed they would probably both be ok.
The ratios listed which are said to be for a KB 4ZD1 & YB 4ZC1-T aren't correct for the 4ZC1-T. The 4ZC1-T uses an "MSG-5H" with the ratios:
3.431
1.963
1.364
1
0.775

So it's pretty close to the "MSG-5C" apart from 5th gear which will just make it rev a little higher on the freeway. The other KB 4ZD1 box "MSG-5E" looks like it has the same wider spaced ratios as a Gemini but should have the 27 spline output shaft the same as the Piazza box.

Post by **Piazza_man** » Fri May 25, 2012 8:20 pm

I've just coppied over some of Rodeobob's relevant figures that you've been referring to and altered it to reflect what you were just saying:
MSG5C
3.413
1.969
1.364
1.000
0.855
R3.402
KB 4ZD1

MSG5E
3.785
2.171
1.413
1.000
0.855
R3.753
KB 4ZD1

MSG5H
3.431
1.963
1.364
1.000
0.775
R3.402
YB 4ZC1-T

Is this correct Bugle?

rodavo · Post by **rodavo** » Fri May 25, 2012 10:58 pm

Just some history for you. I was actually dilligent with that box and had the oil replaced with the addition of lucas oil stabiliser about a year before I stopped driving it. Don't forget that box has quite a few km's on it (its the original box), it did have a slight leak, but I did keep a check on it and topped it up when I was driving it regularly.

Further to this, I do have a spare low kilometer Piazza gearbox I am looking to sell. It came out of a sub 100,000 km vehicle, but obviously I have never used it so can't say what condition it is in internally. Let me know if you are interested. I also have an LSD rear end from the same car that is also up for grabs.

Post by **Piazza_man** » Fri May 25, 2012 11:38 pm

Hey Dave,
Yeah this gearbox was on its last legs unexpectedly and there was nothing to indicate a bad leak either. Sorry if I came accoss a bit blunt, but I really didn't need that news. On top of that the diff is all but shagged too. Just old age I'm told. Both the gearbox and diff are out with the car up on a hoist. The steering rack also has to be replaced due to an oil leak, so that will have to be dropped very soon. I also asked the fuel tank to be dropped and cleaned out, along with the fuel lines. Nothing like fresh and newly built undercarriage I say. I need a really strong and reliable drivetrain because of the direction I'm heading with it.

I tell you what I might need that spare gearbox and diff if that's OK. I've just gotta find out where the boys are up at the diff specialist and if that Rodeo gearbox at the other specialist has arrived and will work. I'll have a better idea on Monday, and I can text you then.

What do you think of the new spoiler and front end?

rodavo · Post by **rodavo** » Sat May 26, 2012 12:06 am

Yeah no worries. Keep me posted with what you want to do. Unfortunately the car is getting on and things do wear out. I had the steering rack replaced not long after I bought the car with the one out of my old blue piazza which had alot lower km's because the original one had worn out steering arms.

You may also be interested in the steering rack I have in my shed which came out of a low low low km imported Piazza (less than 40,000km). It was actually one of the higher spec Jap piazza's (the same car that those square headlights came from which I gave you) so I am not sure if it has a better rack ratio for sportier feel or not? But its in really really good condition.

I also have the larger diameter front anti roll bar from this car and a few other bits and pieces. I need to sell all my piazza bits to make room. Just haven't got around to advertising it all.

If your looking at the fuel system, you might want to look at the fuel pump hose routing that feeds the pump as I was never happy with how I did it for the bigger Bosch pump. It works but is not ideal. I have a small surge tank here that I bought for it and I was always going to fit the surge tank with a low pressure Carter pump to feed it but never got around to it.

In terms of the new spoiler and front end. Cant say I am a fan of the rear spoiler, I never have liked the look of them on Piazza's. But I like the look of the square headlights. My preference would be the standard bonnet with the eyelids and the square headlights, but doesn't look too bad with the bulged. To be honest, I loved the look of it when I sold it to you.

Post by **wedgenut** » Sat May 26, 2012 5:23 am

I have a piazza gearbox currently dismantled, if you send detailed info on your requirements, pictures, drawings gear tooth and bearing sizes etc I can see if it lines up with what I have. All parts are in good order.

Post by **Piazza_man** » Sat May 26, 2012 9:05 am

Thanks Wedgy. I'll talk to the gearbox guy on Monday.

Bugle · Post by **Bugle** » Sat May 26, 2012 1:25 pm

eyecon wrote:I've just coppied over some of Rodeobob's relevant figures that you've been referring to and altered it to reflect what you were just saying:

Is this correct Bugle?

Yep looks correct

Post by **Piazza_man** » Sat May 26, 2012 3:55 pm

rodavo wrote:Yeah no worries. Keep me posted with what you want to do. Unfortunately the car is getting on and things do wear out. I had the steering rack replaced not long after I bought the car with the one out of my old blue piazza which had alot lower km's because the original one had worn out steering arms.

You may also be interested in the steering rack I have in my shed which came out of a low low low km imported Piazza (less than 40,000km). It was actually one of the higher spec Jap piazza's (the same car that those square headlights came from which I gave you) so I am not sure if it has a better rack ratio for sportier feel or not? But its in really really good condition.

I also have the larger diameter front anti roll bar from this car and a few other bits and pieces. I need to sell all my piazza bits to make room. Just haven't got around to advertising it all.

Dave
PM sent mate.

Post by **Piazza_man** » Fri Jul 13, 2012 10:15 am

Just read the '81-'84 I-Mark Deluxe coupe as sold in North America uses the same MSG-5H box, as was the JDM Gemini 1.6lt with the G180 motor. You can now add that car to the small list of cars having the same gearbox 5H designation.

But wait there's more...
http://www.automobile-catalog.com/car/1 ... turbo.html

On this site it says the '86-'88 Australian spec Piazzas used the MSG-5N boxes. WTF! The ratios are all the same as the 5H but the 1st gear ratio is 3.174 on the 5N. Now I'm confused. Can this be true, ignoring the fact the same website says the Piazza is a FWD.