How to Change the Transaxle Fluid
- Thread starter Tavalin
- Start date
There are two plugs on the driver's side of the transmission housing. Upper is the fill, lower is the drain. Be sure to open the fill first just to make sure it opens. You don't want to end up draining only to find you can't refill it.
So, open the refill port, position your drain pan and open the drain port. Once empty, put the plug back in the drain port. Pour the fresh fluid in the fill port until it starts to drip back out.
If you jacked the car up to drain, you should put it back on the ground for the fill phase.
So, open the refill port, position your drain pan and open the drain port. Once empty, put the plug back in the drain port. Pour the fresh fluid in the fill port until it starts to drip back out.
If you jacked the car up to drain, you should put it back on the ground for the fill phase.
Steve Hoelscher
True Classic
Be sure the car is sitting level when you fill it. Also, a funnel with a length of hose, from the funnel that will fit into the fill plug opening, makes filling way easier. Position the funnel next to the water tank and look down at the fill hole to see when it runs out.
Use only Redline MTL.
Use only Redline MTL.
You can get Redline at Summit Racing or Amazon. Before you use the NAPA fluid, tell us what it is specifically. Using the wrong gear oil can have a less than desirable outcome.
Tavalin
Florida Mike (again)
JimD,
This is what they said was the same gear oil as Redline:
Is this the correct oil?
I don’t think it is European.
Mike
Steve Hoelscher
True Classic
No, its not. Not even close. I would highly discourage using that. Take it back and get a refund. Thank them for the referral. It is in fact GL-1, which is the factory specified oil but you DO NOT want to use that.
You can buy Redline MTL from any number of online retailers. Amazon has it:
https://www.amazon.com/Red-Line-Transmission-Transaxle-Lubricant/dp/B000CPCBEG/ref=sr_1_2?crid=OF7QYZYA2YLH&keywords=redline+mtl&qid=1561428059&s=gateway&sprefix=Redline+MTL,aps,125&sr=8-2
There is nothing that "...is just like Redline MTL". Except for maybe Redline MT-90.
If you are desperate, if you can find Castrol or GM Synchromesh fluid, that would be an acceptable alternate.
As for service intervals, if you have a car that has the original gear oil in it, it needs to be changed, regardless of mileage. In fact, it would be rare now-days for any of these cars to be used enough to need the gear oil serviced do to mileage. I recommend changing it every three to four years depending on use. If you use the car more regularly, it can go longer between service intervals. This is because the gear oil needs to be heat cycled regularly to boil off the condensation that collects in the case when the car sits. That condensation contaminates the oil and causes it to break down. Thus it doesn't last as long.
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Steve Hoelscher
True Classic
Pro tip: When changing your gear oil DO NOT use an impact to tighten the drain and fill plugs. They are pipe threads that taper so over tightening them will crack the case.
Steve, With all due respect, why should X owners all switch/use Redline MTL over factory spec GL1 when Redline MTL causes gasket leaks? TonyK recently posted how he placed cardboard under his trany after putting Redline in it and cause the gaskets to fail with leaks appearing on the cardboard. It seems Redline causes more damage than it is worth.
Tavalin
Florida Mike (again)
Okay, all wonderful advise but now I am confused.
Knowing that the 1986 X that “Gary” owns has the original oil still in it, what should I use?
GL1 or Redline MTL or something else entirely different?
Not wanting to start an argument. I really need to know what would be best for this old transaxle for the first gear oil change. Using the incorrect one can be more detrimental than one that has been maintained, going to an oil that is too loose or one that is too tight.
I really need to know which gear oil would be the best for my situation. Adding in the oil that would be best for a well maintained transaxle might not be the best for a neglected one.
Please help... I am going back to NAPA this week end to return the gear oil I ignorantly purchased.
Thanks everyone. Looking forward to your suggestions.
Mike
Knowing that the 1986 X that “Gary” owns has the original oil still in it, what should I use?
GL1 or Redline MTL or something else entirely different?
Not wanting to start an argument. I really need to know what would be best for this old transaxle for the first gear oil change. Using the incorrect one can be more detrimental than one that has been maintained, going to an oil that is too loose or one that is too tight.
I really need to know which gear oil would be the best for my situation. Adding in the oil that would be best for a well maintained transaxle might not be the best for a neglected one.
Please help... I am going back to NAPA this week end to return the gear oil I ignorantly purchased.
Thanks everyone. Looking forward to your suggestions.
Mike
Steve Hoelscher
True Classic
Lubrication technology has come a long way since Fiat spec'ed GL1 for the SOHC transmissions back in the late 1960s. More than 50 years ago. If you are happy with how your transmission works and using 60+ year old oil technology we can stop here. If not...
General perception is that synthetics tend to leak more than petroleum oils. I have heard the complaints that "I replaced my GL1 with MTL and now it leaks". Based on the dozens of units I have been into I would bet that the GL1 was also leaking it just wasn't as obvious. Synthetics flow more readily and therefore _could_ potentially be more prone to leaks but if the case was properly sealed it won't leak regardless of the oil used.
I should note that; a leak is not "damage". Where as MTL will lengthen the life of the various components inside the transmission over GL1, characterizing a leak, assumed to be due to MTL, causing "damage" or "gasket failure" is a miss characterization of the reality of the two fluid's performance. Note: I typically don't use gaskets in the units I build.
Fact: I have personally tested a wide range of gear oils. GL1, various motor oils (both petroleum and synthetic), various gear oils (both petroleum and synthetic). I have tested the name brand gear oils and synchromesh fluids of various weights, even ATF. I have tested these in both street cars and racing applications, and in various transmissions including dozens of X1/9 4 and 5 speeds. I also build other transmissions for specialty applications. Some street and many are performance or racing applications. I have build Toyotas, Hondas, Fords, GMs, BMWs and quite a few Alfas, Ferraris and even a Lamborghini. The Honda units are the only ones that I don't recommend Redline oils for (and there is a specific reason due to materials). I recommend Redline products because they perform better than anything else I have tested. There are others that are nearly as good, I previously noted Castrol and GM Synchromesh Fluid as very good alternates, but none are better. And I don't see problems with leaks on units I build.
I use MTL in my own X1/9s and have for decades. I also use it in both my Toyotas (street car and race car). No leaks from those either.
If you want to get the most life and performance from your X1/9 transmission, use MTL. I have the data to document that statement. Or don't. You asked for advise and I offered mine.
General perception is that synthetics tend to leak more than petroleum oils. I have heard the complaints that "I replaced my GL1 with MTL and now it leaks". Based on the dozens of units I have been into I would bet that the GL1 was also leaking it just wasn't as obvious. Synthetics flow more readily and therefore _could_ potentially be more prone to leaks but if the case was properly sealed it won't leak regardless of the oil used.
I should note that; a leak is not "damage". Where as MTL will lengthen the life of the various components inside the transmission over GL1, characterizing a leak, assumed to be due to MTL, causing "damage" or "gasket failure" is a miss characterization of the reality of the two fluid's performance. Note: I typically don't use gaskets in the units I build.
Fact: I have personally tested a wide range of gear oils. GL1, various motor oils (both petroleum and synthetic), various gear oils (both petroleum and synthetic). I have tested the name brand gear oils and synchromesh fluids of various weights, even ATF. I have tested these in both street cars and racing applications, and in various transmissions including dozens of X1/9 4 and 5 speeds. I also build other transmissions for specialty applications. Some street and many are performance or racing applications. I have build Toyotas, Hondas, Fords, GMs, BMWs and quite a few Alfas, Ferraris and even a Lamborghini. The Honda units are the only ones that I don't recommend Redline oils for (and there is a specific reason due to materials). I recommend Redline products because they perform better than anything else I have tested. There are others that are nearly as good, I previously noted Castrol and GM Synchromesh Fluid as very good alternates, but none are better. And I don't see problems with leaks on units I build.
I use MTL in my own X1/9s and have for decades. I also use it in both my Toyotas (street car and race car). No leaks from those either.
If you want to get the most life and performance from your X1/9 transmission, use MTL. I have the data to document that statement. Or don't. You asked for advise and I offered mine.
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Tavalin
Florida Mike (again)
Steve,
So basically what you are saying is that if my 1986 X1/9 has never had a transaxle oil leak and has never had the gear oil changed the Redline MTL should be good not only now but for the long haul if I stay up on the maintenance.
If Redline MTL is synthetic what would be the mileage or months between changes? Also, does Redline MTL conduce moisture or is that just something naturally that occurs in the metal transaxle when it sits for long periods at a time?
I really appreciate your knowledge and recommendation. If I had as much experience as you do I would be dog tired by now...lol.
I will return the NAPA GL1 and purchase the Redline MTL.
Thanks,
Mike
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Tavalin
Florida Mike (again)
Also,
When I had a semi-hi-performance 1989 Mazda MX6 GT turbo with a race cam, better fuel pump and larger injectors, I switched to Mobil 1 and used it exclusively ever since. I switched from Royal Purple which is what everyone else at the time was using and the difference in the turbo was noticeable, more boost and smoother and actually quieter.
I also was wondering at the time about the cycle of synthetics. So I called the number on the side of the oil bottle that stated something about questions. They referred me to another number. It actually happened to be the Mobil 1 engineers. What they told me shock everything I knew about oils and oil changes for the rest of my life.
The engineer stated that Mobil 1 has been tested for many years in many different applications. He stated that their oil “doesn’t break down” and has a life span of about 70000 miles. He only recommended changing out the oil filter per the manufacturer recommendations and topping back off. Well, I wouldn’t want to experiment on my Mazda so I changed my girl friend’s at the time oil, a 1991 Mazda 626 with Mobil 1 and only changed the oil filter every 5500 miles. After about 2 years of that and about 30000 miles I got scared and changed her oil. It was still golden when it came out. I was sold on Mobil 1. Oh, and she never found out that I used her car as a testbed.
It only makes sense that synthetics would be different than normal petroleum based oils. I just didn’t know by how much different.
Now, fast forward from 1992 to today and low and behold, Mobil 1 has a 100000 mile guaranteed oil.
Makes you wonder what makes it different from the non-100000 mile Mobil 1 oils???... hum.
Sorry, I digress,
Mike
When I had a semi-hi-performance 1989 Mazda MX6 GT turbo with a race cam, better fuel pump and larger injectors, I switched to Mobil 1 and used it exclusively ever since. I switched from Royal Purple which is what everyone else at the time was using and the difference in the turbo was noticeable, more boost and smoother and actually quieter.
I also was wondering at the time about the cycle of synthetics. So I called the number on the side of the oil bottle that stated something about questions. They referred me to another number. It actually happened to be the Mobil 1 engineers. What they told me shock everything I knew about oils and oil changes for the rest of my life.
The engineer stated that Mobil 1 has been tested for many years in many different applications. He stated that their oil “doesn’t break down” and has a life span of about 70000 miles. He only recommended changing out the oil filter per the manufacturer recommendations and topping back off. Well, I wouldn’t want to experiment on my Mazda so I changed my girl friend’s at the time oil, a 1991 Mazda 626 with Mobil 1 and only changed the oil filter every 5500 miles. After about 2 years of that and about 30000 miles I got scared and changed her oil. It was still golden when it came out. I was sold on Mobil 1. Oh, and she never found out that I used her car as a testbed.
It only makes sense that synthetics would be different than normal petroleum based oils. I just didn’t know by how much different.
Now, fast forward from 1992 to today and low and behold, Mobil 1 has a 100000 mile guaranteed oil.
Makes you wonder what makes it different from the non-100000 mile Mobil 1 oils???... hum.
Sorry, I digress,
Mike
Steve Hoelscher
True Classic
Mike,
You are right about synthetics. The 3000 mile oil change interval was a marketing campaign by Jiffy Lube (the first commercial oil change chain store). See how effective marketing can be? That said, today most auto manufacturers recommend between 7500 and 10,000 mile service intervals on engine oil. Heck, my new Ford Super Duty has an intelligent oil life monitor and has been flagging engine oil changes at 9500 miles. This on a modern diesel pickup that tows a big enclosed car hauler 50% of the time.
Also, I have been using Mobil 1 engine oil in my street cars and race cars for many years. I have been very happy with its performance. I started using Redline back in the early 90s when I was really beginning to learn automotive engineering and was doing lots of experimenting with X1/9 transmissions. It was 1996 that I went to work for a Pro Racing team (as the team engineer) that had Redline as a sponsor. There I learned a lot about their products and spent a lot of time talking with their engineers. I was already sold on MTL but learned a lot about synthetics and Redline's products specifically. I have used lots of others over the years but always went back to Redline for transmissions and differentials.
Synthetics and petroleum oils both can be contaminated by moisture. Engines and transmissions are vented by necessity and as the weather changes moisture naturally condenses out inside the engine and transmission. That moisture settles into the lubricant. It will be boiled off once the oil reaches normal operating temperatures and can stay there long enough for the moisture to be fully expelled. However, long periods of storage and shorter trips promote contamination and don't burn off the moisture. Over time the oil gets contaminated. Synthetics are less likely to varnish than petroleum oils so they last longer but they are still effected.
As noted above, the average collector doesn't daily drive his car. It sees occasional use and that is often a short trip to cars and coffee. Or a saturday run to the store or dinner. That's not an hour of good hard use to really exercise the car and heat the fluids. Change the engine oil annually and the gear oils every 3 to 4 years. Gear oils can go further if the car is used more regularly. This is all out the window if the car is tracked.
You are right about synthetics. The 3000 mile oil change interval was a marketing campaign by Jiffy Lube (the first commercial oil change chain store). See how effective marketing can be? That said, today most auto manufacturers recommend between 7500 and 10,000 mile service intervals on engine oil. Heck, my new Ford Super Duty has an intelligent oil life monitor and has been flagging engine oil changes at 9500 miles. This on a modern diesel pickup that tows a big enclosed car hauler 50% of the time.
Also, I have been using Mobil 1 engine oil in my street cars and race cars for many years. I have been very happy with its performance. I started using Redline back in the early 90s when I was really beginning to learn automotive engineering and was doing lots of experimenting with X1/9 transmissions. It was 1996 that I went to work for a Pro Racing team (as the team engineer) that had Redline as a sponsor. There I learned a lot about their products and spent a lot of time talking with their engineers. I was already sold on MTL but learned a lot about synthetics and Redline's products specifically. I have used lots of others over the years but always went back to Redline for transmissions and differentials.
Synthetics and petroleum oils both can be contaminated by moisture. Engines and transmissions are vented by necessity and as the weather changes moisture naturally condenses out inside the engine and transmission. That moisture settles into the lubricant. It will be boiled off once the oil reaches normal operating temperatures and can stay there long enough for the moisture to be fully expelled. However, long periods of storage and shorter trips promote contamination and don't burn off the moisture. Over time the oil gets contaminated. Synthetics are less likely to varnish than petroleum oils so they last longer but they are still effected.
As noted above, the average collector doesn't daily drive his car. It sees occasional use and that is often a short trip to cars and coffee. Or a saturday run to the store or dinner. That's not an hour of good hard use to really exercise the car and heat the fluids. Change the engine oil annually and the gear oils every 3 to 4 years. Gear oils can go further if the car is used more regularly. This is all out the window if the car is tracked.