Type 9 or MT75 gearbox

[hilux]

My 2.0L VX engined car was built by someone else using (I believe) second hand parts. Its an SEI with independent rear so I assume sierra running gear.....

The gear box plays up now and again when hard charging and changing up into 4th. so I may have to change it. (there is no problem if I slow the change, is this normal?  

1)  Whats the difference between type 9 and MT75 boxes, what are they from? Are they interchangeable?

2)  Is it worth having my box reconditioned or simply replaced.

3)  If changing box is getrag box better ?

Thanks in advance

[DutchWestfield]

Hilux,

I have found a website where images of both boxes can be found: http://www.zetecinside.com/xr2/gearbox.htm

This site has images of many other gearboxes that will fit a Zetec. The MT75 is the box that replaced the Type9. Type9 is (partly) cast iron, MT75 is full alloy. The MT75 can be disthinguished easily from the Type9 because it has strengthening ribs on the (integrated) bellhousing. I found this the easiest way to find the box of choice at the scrappies (MT75 in my case).

The Type9 box is less wide than the MT75, therefore you can move the engine further backwards in the chassis, this should give a better weight distribution. Furthermore, for the Type9 different gear ratios are aviable for a reasonable price. I choose the MT75, because it is the more modern box and I do not expect that I want to change ratios in the near future. I do not concider myself to be a experianced enough driver to have any benefit from the better weight distribution  

It might be worth reconditioning your box, or exchange it for a reconned box. probaly the cheapest route if you ask me..

Regards,

Bertram

[Mark Stanton]

The chassis is different for an MT75 gearbox - it has a wider tunnel.    

If you have a Type 9 gearbox - then stay with it - get a new one or refurb what you have.

To fit an MT75 will require the wider transmission tunnel    

If by chance you do have a chassis made to fit an MT75 - still stay with the Type 9 - as you can get the engine much further back    

[hilux]

Thanks guys,

very helpful info

So westfield chassis differ for either box

So my SEIW will only take type 9 box (if fitted, I`ve yet to check) and will not take MT75

How strange.......

[Matt Seabrook]

You will not be able to fit an MT75 box to your Vx as the bell housing has a different stud spacing the type 9 has a removable bell housing and can be changed for one that will fit your Vauxhall. Before any body is going to say you can fit an MT75 by doing x or y anything is possible it just ant worth it the type 9 is the best box.  

[hilux]

Thanks Matt

the problem is only when changing from 3rd to 4th quickly, it graunches  and baulks in between gears

if changing gear slower it seems fine (dont all say "change gear slower then, you prat")

Does anyone else find this normal or are your type 9 boxes like a hot knife through butter

Thanks in advance

[Matt Seabrook]

It sounds like the syncro is worn sorry. What revs are you changing at?

[rowle1p]

I have the same problem with my MT75, only experienced when changing from 2nd to 3rd, quickly at high revs, the gear will not locate.  Yes.......  if you change slower there is no problem.  Is this cos the MT75 as standard is not capable of a quick change ?  I am able to change quick between other gears.

If the box does need synchro repairs, does anyone know of a company which can assist ? (Leic area)

Cheers

[Matt Seabrook]

The box should go through unless you are using very high rpm. I had a problem getting 2nd gear at a resent drag race but the the engine was getting upto nearly 8000rpm. When the box was in the Sierra 6500rpm was the rev limet. Unless the box is in good working order you may get some problems when realy pushing on.

[ACW]

As already mentioned if you have a Vx motor then you will have to stay T9 or use a Manta Gearbox and you just dont wanna do that.....

Vx revs a little to high for a standard T9 box unfortunately and id does sound like you have a bulk ring / syncro problem starting to show. Unfortunately EP type gearbox oils are great for helical cut gears but the last thing in the world you want to bathe your syncros in. As a medium turn work around I would drain out the existing oil, flush the box and fill with a sythentic heavy motor oil.  This would clean the EP coating off the syncros and speed them up a bit.

This will result in higher gear wear but your gonna have to swap the box before too long and for fast road use the change of oil may well give you another year or even longer.

To drain the box you need a suction pump and some hose to suck it out from the bottom of the box through the top cover.

[hilux]

Thanks for advice..

Matt,

This all happens at high revs, 5-6K and a quick shift.

Blip throttle and downchange is no problem though

.........................................

Coupla questions Adrian.

What is `heavy` motor oil.

Why is there no drain plug

If I refurbish box couldnt I tap in a drain plug while its out of car?

Hilux  

[Fast Westie]

Hilux

The synchros on the type 9 are a bit weak anyway and are prome to breaking in race situations! Quaife do steel baulk rings for them, but is you have a box with roller bearings on the main shaft you should be alright. My MT75 also graunches on a fast change!

Heavy motor oil would be 15W50.

There is no drain plug on the type 9 because in normal use there was no need to drain the oil. You can drill and tap one in to make oil changes easier.

[Matt Seabrook]

If a blip on the throttle on the change down stops the graunching the it is almost certain that it will be worn syncro`s. What you are doing by blipping the throttle is matching gear speed to road speed and this is allowing it to go into gear. This is the job of the syncro and this would indicate that the problem is with the syncro.

[hilux]

Fast Westy

How will I know if I have roller bearing box

I assume shaft bearings obvious when out of car, but what other bearings are used, ball type? is there gearbox ID that can tell me?

Matt

Blip on down change is to match gearbox speed and engine speed quicker without clutch slip, downchanges are fine??

Thanks in advance  

[hilux]

PS isnt `graunch` a great word..... almost anglo saxon

"ever had a good graunch?"