How to Change the Transaxle Fluid

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.

Steve, I have been using the oil monitor in our 2010 2.4L Ecotec for oil change intervals since we bought it in 2011. As you say it gives you 10K oil changes. I'm using "conventional" oil, not pure synthetics.
(Mostly Valvoline)
 
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.
Steve,
Thanks for the information. It all makes sense. I am by no means an expert but very OCD and want to study and ask questions before I jump into something I am not sure of (my wife says is a flaw).
I believe in measuring twice and cutting once, 80% is not good enough, think harder not smarter.
I believe that I will stick with full synthetics for all gear oil and engine oils for the X (Mobil 1 and Redline).
The cheap NAPA gear oil (which probably a good oil for for the proper purpose) is going back. I still have the receipt.
Thanks again for the mentorship,
Mike

Steve, one more thing... when I finally dig into the X, please talk me down from the Bring a Trailer anger. Sometimes the Marine comes out when I am hot, sweaty and can’t get a bolt off or smash my hand... lol
 
Just want to mention Steve's comment of GL1 and condensation and perhaps rust. I believe that most retail GL1 purchased is basic GL1. Certain brands of GL1 have different additives. You usually have to buy in bulk (35 lb pail) and cost about $100 which is not that bad. Chevron Gear Oil GL1 are "rust and oxidation inhibited gear oils." If GL1 is so bad then why are they manufacturing and selling it in bulk where Chevron seems to be targeting the high mileage trucking industry? Also, GL1 is nothing more than baby oil without the scent.

https://cglapps.chevron.com/msdspds/PDSDetailPage.aspx?docDataId=406136&docFormat=PDF
 
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I never said GL1 didn't have its applications. i said it wasn't what you wanted to use in your X1/9 Transmission given the advancements in oil technology over the last 60 years. And yes, GL1 can and probably has benefited from modern formulation and additives. But its still GL1 and therefore its performance is comparatively lacking.

I didn't mention rust but I have seen rust inside some transmissions that were filled with GL1. I should note that I have never seen rust in a transmission with MTL/MT90 but then that's not a very big data set and its less likely that a transmission filled with Redline would have sat neglected for so long.

Any oil can become contaminated by condensation if the conditions are right. Back when I owned an Aamco Center I had a local mom bring her late model Tahoe with less than 20K miles in with a transmission failure. She lived in a subdivision nearby. Her kid's school was only a few minutes away. As was the shopping center where she did most of her shopping. She seldom drove more than a couple of miles at a time. The problem was the transmission fluid never got up to full operating temperature so the fluid never burned off the condensation. It got mixed with the fluid, which in turn ruined the transmission. Gear oil and engine oil have the same problems but only your engine oil gets changed regularly.

Mike, don't hesitate to inquire. These car have been my passion since I saw the first photo of one as a kid.
 
Well,
All I can say is that I do know the benefits of synthetics vs regular. I am going with the Redline MTL because it seems to be closely related to the way Mobil 1 reacted to my semi-high performance Mazda MX 6 GT turbo.
I will keep everyone here apprised of my Redline MTL experience after I change the transaxle oil. At the moment, nothing seems to be amiss. Tight seals and shifts very smoothly. If something changes shortly after I will definitely post here.
My only concern is that once I change the very old oil something might break or a seal will bust.
Only way to find out is by changing it.
If anyone wants to come here to Tampa and assist I much appreciate it.
Also, the NAPA GL1 gear oil bottle says “mineral oil”. So, Torino is correct as it being baby oil...lol Which I have a lot of experience with since I have a nine year boy and a 2 month old boy.. :)

Steve, sounds like you have been around awhile. My trust in your experience is well taken. Thanks for being passionate in what you know and the products that you trust.
Mike
 
Mike, since you're new to the forum, I'll tell you that many of us here have been with these cars since the beginning. I bought my first X1/9 in January of 1979, a '75 model. I was in high school and it was my first car. I have owned at least one X1/9 ever since. I learned every phase of wrenching on these cars. First was simple maintenance. Oil changes, etc. Then minor repairs, then major repairs, full restorations and full racecar builds. I learned all about transmissions by having to fix my '77 X's transmission myself because, as a poor college student, I couldn't afford to pay someone else to do the work. Later I learned competition driving and racecar engineering on these cars. Something that has provided me a pretty good living for the last 20 years. I won 4 SCCA National Championships in X1/9s. My transmission experience, without any effort on my part, developed into a (hobby) side business that has spanned three decades. After starting to track the units I built I have logged over 100 units. I suspect I have built more X1/9 (128/Yugo) transmissions than anybody else outside of Fiat's Manufacturing operations. And that doesn't include the other types I have also built. I owe these cars and this community a lot. I always enjoy the opportunity to give back. :)
 
Steve, I have been using the oil monitor in our 2010 2.4L Ecotec for oil change intervals since we bought it in 2011. As you say it gives you 10K oil changes. I'm using "conventional" oil, not pure synthetics.
(Mostly Valvoline)

Yup. My truck's OLM monitors how the truck is driven and not the condition of the oil. I use Rotalla T6 in it (full synthetic). I assume the OLM doesn't know the difference. Incidentally, an oil change uses 15 quarts at $22/gallon and a $20 oil filter. So doing it myself costs me $100 for each change. Add to that a $50 for each of the air and fuel filters (30K service intervals).

rest stop F250.jpg
 
Jim, thanks for posting that. That's the late Dennis Cipriany, my co-driver next to me. Dennis was another X1/9 autocrosser. He co-drove with me for many years. I forgot how ugly the MR2 was then. This is what it looks like now. The only thing it shares with the car in the pic above is the original tub.

Also a pic of my Championship X1/9.

shoelscher-1.jpg

PeruTour3.jpg
 
Mike, since you're new to the forum, I'll tell you that many of us here have been with these cars since the beginning. I bought my first X1/9 in January of 1979, a '75 model. I was in high school and it was my first car. I have owned at least one X1/9 ever since. I learned every phase of wrenching on these cars. First was simple maintenance. Oil changes, etc. Then minor repairs, then major repairs, full restorations and full racecar builds. I learned all about transmissions by having to fix my '77 X's transmission myself because, as a poor college student, I couldn't afford to pay someone else to do the work. Later I learned competition driving and racecar engineering on these cars. Something that has provided me a pretty good living for the last 20 years. I won 4 SCCA National Championships in X1/9s. My transmission experience, without any effort on my part, developed into a (hobby) side business that has spanned three decades. After starting to track the units I built I have logged over 100 units. I suspect I have built more X1/9 (128/Yugo) transmissions than anybody else outside of Fiat's Manufacturing operations. And that doesn't include the other types I have also built. I owe these cars and this community a lot. I always enjoy the opportunity to give back. :)
Steve,
I really wouldn’t say I am new to the forum but I am still learning. With a full time job, a nine year old (that says the X1/9 is his) and a new born I don’t have the time I would like to have to keep restoring the X plus the money to purchase everything I need all at the some time. I get it done and keep it safe to drive because of my precious cargo.
Everyone here pretty much knows of my first trials and tribulations and some of the neighborhood children in Bellevue, Nebraska learned a couple of words they probably shouldn’t have. I have been a member since 8/2015 (formally known as Nebraska Mike) which is not as long as some folks here but I value all of your expertise and love to read about your experiences and why someone owns an X1/9. Sometime the “why” is better than any book I could read.
Thank you for sharing,
Mike
Again, anyone is welcome to come down to sunny Florida to assist me with the install of all the parts.. just ask’n.
 
Okay everyone!!! I finally got the fill plug broken free and as soon as I did the fluid gushed out like it was a drain plug. I had the driver’s side lifted so I don’t think it should have done that. After I broke free the drain plug more fluid of course gushed out. I leveled the X and let the fluid drain out for about a half an hour. I got over 5 quarts of fluid out. Then I put in about 4 quarts when it started to drip out if the fill plug. The drain plug was full of metal shavings and the fluid was very stinky and grey color. Buttoned it up and drove it to test my work. It shifts so smooth now. but then the timing is now a problem that I have in another thread.
Thanks for all the advise and help. I used Redline MTL fluid.
Mike
 
First remove the filler so you know you can refill it and then remove the drain.

View attachment 23048

The plugs usually have a dimple in them so they don’t look like bolts. They may have an Allen key internal head instead of being a hex head.
Is this the 5 speed in your picture? If so, any idea if the fill plug is in roughly the same spot on the 4 speed? Looks the same, except for the fill-cap they’ve used:

A2909C56-5930-4516-AE3A-7914556D5189.jpeg
 
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