5-Speed Swap Info

[twistedsymphony]

Before I even bought my VX I lamented the fact that it was never made in anything but an automatic... I thought surely a 5 speed swap would be a popular modification considering it's performed commonly on other collectors cars that were auto only, or mostly made as an auto.

I was also surprised that I couldn't find a single person who had done a 5-speed swap save a few pictures of racing spec VXs.

Since any real info on this was fairly non-existent I decided to look into the feasibility myself and see what would be involved. Obviously with the VX sharing so much with other Isuzus that's the first place to look. Also with other Isuzus being more common I decided to start looking for information there to see if someone had done a swap on a different vehicle with a similar setup.

http://forum.planetisuzoo.com/viewtopic.php?p=159566

What I learned
Troopers that used the 4L30E Automatic and TOD used the MUA5 transmission as the alternative options... the 5 speed (from what I've been told) was only available with the 3.2L and the transfer case is integrated into the transmissions... meaning that if you used that transmission you would lose the TOD system as well

using MUA5 you will need the 3.2L bell housing (which should be direct bolt on) as well as a flywheel from a 5-speed 3.2L and the 3.2L clutch/pressure plate.

The factory transmission cross-member is apparently the same between the two transmissions so no customization is needed there either.

Another thing I learned is that the VX shares a firewall with the Amigo... this means that you could use a clutch pedal, Clutch Master Cylinder, and 5-speed Brake pedal from an Amigo and the mounting locations should exist (you will probably need to drill some bolt holes though). You might also be able to use the clutch lines from an Amigo as well, though I'm not entirely sure on that.

The driveshaft length will change, meaning you'll have to have a custom one made... this usually costs about $200-$300 for a steel one and $400-$500 for an aluminum one (aluminum drive shafts will improve your mileage and acceleration BTW)

I'm not sure if the MUA5 uses cooling lines if it doesn't the existing transmission cooling lines need to be capped or removed, if it does use them it will need to be adapted.

The two things left after all of this is the computer and the internal trim... I'm not sure if the center console shifter area is shared with the 95-97 Rodeo like the dashboard is... if it is shared then you're probably only looking at swapping some plastic for an OEM look.

As for the computer, again I'm not sure if the computer is similar to that of the trooper, if it is then you could simply swap it out... if not you will likely need to do some sensor fooling to make the computer assume that the auto transmission is a-ok.... I'll have to look more into this aspect...

-----------------------------
I apologize if this work has already been done once before. I looked for a couple of weeks to find GOOD 5-speed swap info on the VX to no avail... after doing research myself I managed to find all of the above in 2 days by asking questions to a few key people in the Isuzu community.

I have no plans to do this swap right now, I don't jump into projects like this until I know the feasibility and all the info about what has to be done.

I'll post more when I figure it out, but I'm waiting to receive my FSM... when that comes in I should be able to determine what needs to be done on the Computer side of things.


Another interesting link I found on engine swaps is here:
http://myweb.cableone.net/bcanderson...uroraSwap.html

This is beneficial to anyone interested in replacing the motor but NOT the transmission.

[twistedsymphony]

Doing a little more research I was able to determine that the Rodeo shifter trim should work for the VX... the new 5 speed wont need transmission cooling lines so they can be capped off and the Trooper 5 speed computer should work for the VX...

Parts list is as follows:
-MUA5 Transmission with 3.2L/3.5L Bell housing
-3.2L/3.5L Clutch & pressure plate (should be bought new)
-3.2L/3,5L Clutch Slave Cylinder (should be bought new)
-3.2L/3.5L 5 speed flywheel
-Brake Pedal from a 5 speed Rodeo (or saw off half of the auto pedal)
-Clutch Pedal from a 5 speed Rodeo
-Clutch Master Cylinder from a 5 speed Rodeo
-Clutch line from a 5 speed Rodeo? (go with SS braided line if possible)
-Computer from a Trooper with the 3.5L 5 speed
-Interior Shifter Trim from a 5 speed Rodeo
-Custom Drive-shaft

I'm thinking you could get the job done for ~$1000-$1500 +installation depending on how much you could find the parts for.

MUA5s go for ~$500 with the next most expensive item being the custom drive shaft...

This would be a complete bolt-on project with the exception of drilling a few holes to mount the clutch pedal... you'd lose TOD but you'd gain a bullet proof transmission/t-case that would not only allow for 2WD and Full-time 4WD but you'd probably have a quicker VX along with much improved gas mileage.

[ZEUS]

All this is interesting... So the 3.5 and 3.2 bellhousings interchange then? Joe Black is pretty knowledgable in all things Isuzu and I know he had some pics of the firewall and pointed out the "cutouts" for the clutch pedal assembly and all that. Otherwise, I haven't heard any real mention of swapping a manual into a VX. I wonder if the transmission tunnel on the VX would be tall enough to fit the manual tranny... Do you know anything about that yet or did I miss it? The use of a manual tranny may be a good route for swapping in a solid axle... and for using a lower low range gear ratio!

[twistedsymphony]

I haven't investigated if a 5-speed will fit in the tunnel.. all of this info is from talking with Isuzu off-road people who have done various engine/transmission swaps and know which parts are compatible with what.

However with nearly every other vehicle I've seen the Automatics take up quite a bit more space than 5-speeds, so I'm not to worried about that.

Not to mention Manufacturers typically build their chassis to handle either, even if they never plan to release one or the other, if trends take a sharp turn tomorrow and they discover that automatics kill kittens and everyone wants a stick shift, they want to make sure they don't have to re-engineer the whole thing

I kind of really want to do this now, but I wont be able to do any of this until next spring at the earliest. If all goes well it would only take a weekend to do, if something goes horribly wrong it could take months though and I'll need my VX for the winter (not to mention I've got other projects on my plate right now). I might take this on sooner if it had already been done by someone else... but as they say "the pioneers get the arrows, the settlers get the land" I don't mind being a pioneer, but I can't afford any arrows right now

I was just really interested in the feasibility so I started researching and thought it would be nice to share my results. :gring:

[twistedsymphony]

I got a little more clarification on some items so I updated the list above.

3.2L and 3.5L equipment is completely interchangeable, so bell housing, flywheel, clutch, etc. can come from either or.

flywheel is different from auto to 5 speed so it will need to be swapped.

firewall is from a RODEO not an AMIGO (duh, it has the rodeo dash... of course it would be a rodeo firewall)... I don't know how I got that one wrong...

Also I'm thinking it might be necessary to swap the gauge cluster from an auto cluster to a manual cluster... since you will no longer need the TOD bits nor the auto selection indicator.... you might be able to make due just pulling bulbs.

[ZEUS]

Sounds like it might be best to find a complete '99 5-speed Trooper. You could just swap the motor, trans, computer, and t-case out of the Trooper at your own pace. Only the finishing touches would require finding a Rodeo, it sounds like, so that would be the only junk yard scrounging you would have to do. Selling the left over parts from both rigs might offset the price of buying a complete Trooper. Does computer swapping in a late model Isuzu create problems with emissions though? I know some vehicles won't pass emissions inspection after a computer swap because the VIN's don't match and it throws a code...

[twistedsymphony]

I suppose it would depend on the emissions laws for the particular state.

Not all ECUs store the vin (don't know if the VX does or not) I don't think there is any problem swapping an ECU for another compatible ECU since they do break sometimes... you might even be able to find someone with Isuzu programming equipment who is capable of swapping the vin in the ECU if necessary.

As far as emissions are concerned on a federal level... you're not allowed to remove any of the emissions equipment, and if they need to be replace they must be replaced with OE parts, if OE parts are not availble then they maybe replaced with similarly speced, certified, aftermarket replacements.

It is perfectly legal to swap the engine and transmission out completely HOWEVER the engine must be from the same model year or newer vehicle, it must be an EPA approved motor (that basically means it needs to come from a car originally sold in the USA), and you must preserve all of the original emissions equipment from that motor.

Obviously some states are more forgiving than others, CA is the worst, as everything in the engine bay needs to be CARB approved, so if you do an engine swap your custom headers built to make it fit will cause it to fail ... that doesn't mean you cant do swaps though... I know Hinson Supercars makes a swap kit to put a Chevy LS1 in a Nissan 240sx and they built custom headers and got them CARB approved making the swap 100% legal in CA as long as you use a factory CARB approved LS1 engine with all the original emissions equipment.

I don't see any real issue with swapping just the transmission and computer out, as long as the computer is a "factory replacement" for that motor since depending on how you look at it the ECU is part of the emissions equipment.

I'm in NH and the only form of emissions testing done here is hooking up to the OBDII port and checking for codes, as long as the reading comes back clean you're good to go, they don't even do a sniffer test and pre ODBII cars (1995 and earlier) are completely emissions exempt...

Even if I left the auto computer on there and it threw transmission codes, I believe a good shop with an intelligent tech would realize that the codes he was seeing weren't relevant to the emissions system.... or you could "know someone" I drove a WRX with no emissions equipment for several years and never had a problem getting a sticker... these days I'm trying to stay 100% legal, but at the same time my summer car is a 1995 240sx, and I bought that year specifically so I wouldn't have to worry about OBDII and emissions testing (hey legal is legal).

Most states don't even do emissions though.

[ObsidianDragon]

Theres a rally spec v-cross run by Tubus Racing in Australia with a 5spd of its own, and a quad cam v6 block, aluminum 3.5 like ours. be interesting to see what they might relay to the community

linkage:
http://tubusracing.com/en/index.php?...id=5&Itemid=27

[Vehi-Cross-Az]

pretty much un-related, but being the owner of a 92
Subaru SVX, about 3 yrs ago our group finally mastered
the 5 spd conversion on our cars, but since they did it
many have found the next week link, being the clutch.
Its way more fun to drive, better mpg too, but they do
drive their cars harder and go thru clutches a bit often.

Good info though on your research, good luck.

[twistedsymphony]

pretty much un-related, but being the owner of a 92
Subaru SVX, about 3 yrs ago our group finally mastered
the 5 spd conversion on our cars, but since they did it
many have found the next week link, being the clutch.
Its way more fun to drive, better mpg too, but they do
drive their cars harder and go thru clutches a bit often.

Good info though on your research, good luck.

Those SVXs are cool... one of my college buddies had one that he put an STi 6 speed in. I don't think he owns it anymore.

The older 5 speeds are kind of crappy though (I used to own an 02 WRX myself) the housing around the clutch would wear out and you'd get that "juddering" when starting out from a stop on wet or cold days, then of course the 1st gear synchros would wear out really fast so you'd have to double clutch if you ever wanted to downshift into first.

All problems with the subaru 5 speeds since the mid 90s. I don't think they fixed the design until the 04 models when they migrated to the same "butterfly" synchros and clutch housing design of the 6 speed.

of course the 6 speed wasn't without it's flaws either, nor was the clutch... but if you're going to go through the trouble of swapping out the transmission it's worth spending a little extra coin on an improved aftermarket clutch IMO.

[kodiak]

?

[twistedsymphony]

race car modifications are cool, but not all that helpful.

they have the financial backing to build custom 1 off parts that just aren't feasible for you and I to make use of.

they have no qualms just cutting a new hole in the floorboard to run the shifter and welding over the old one.

If I were building a race spec VX there is no way in hell I would use an MUA5 transmission... it's complete garbage for that application.

HOWEVER for someone like myself who is build a daily driver&weekend off-roader, the MUA5 is the cheapest/easiest/quickest/most OEM like path to getting a 5 speed, and it's more than up to the task for the kinds of things it will be used for.

I can tell you from that picture that neither the clutch nor the brake are ISUZU standard equipment... in all likely hood the transmission is a $12K racing trans with a custom/easily swappable bell housing and transfer case.

those guys rarely ever use off the shelf parts

[technocoy]

I think the most interesting thing about switching to a 5 speed (other than finally having a manual again, YAY!) would be whether or not we can pump the HP on that one vs the fairly weak one we have now.

That would allow SC owners to finally drop those pulley to get a higher PSI and really get some serious muscle going.

As much as I love my TOD I would seriously consider this if I could be back to shifting and get my HP up around 300. mmmm. yay.

[twistedsymphony]

I'd ask some 5-speed trooper owners...

the SC was made for those things as well, so if they're running higher HP through the same 5 speed/t-case then... there's your answer

[kpaske]

Great info, TS, thanks for sharing! I have often daydreamed about doing a complete drivetrain swap in my VX. We've discussed in some other threads the possibility of dropping in a turbo diesel / 5-speed combo from a Trooper, and if I only had the time and expertise I would have done this long ago (BTW if there are any volunteers out there, I could be open to the idea of paying/bartering/trading or whatever for some help! ). Have you considered anything along these lines?