MT82 Ford Additive XL-18 necessary when switching to non Ford oil?
 

Dear forum,

sorry if this has been asked before. But as I am no native speaker, using the search does not yield that good results since I am not sure what words to search for.

This post is not about my trans oil choice, but wheteher adding the additive or not.

I recently got me a Mustang Boss 302 over here in Germany. I am tracking it a lot. I do experience the MT82 shifting issues though, namely 3rd to 4th gear lockout when close to read line.
To solve this, I went through quite a few mods, including a BLowfish shifter Bracket, an oil change to Motorcraft oil plus XL-18 oil additive, a Whiteline transmission bushing insert and finally BMW PU motor mounts (the motor mounts yielding the most noticable improvement btw.)

As I mentioned, I track the car a lot, and thus will be switching to a high performance 75W90 transmission oil (most US oils are not easily available in Germany) from german manufacturer Ravenol.

My question is: Will I need to add the Ford XL-18 additive anyway?

When you guys switch to Royal Purple Synchromax or whatever magic juice you got over there, do you add the additive or not?

I thought I would just try it without the additive at first and add it later if I got any shifting issues.

Thanks in advance for any advice!

Best regards

Oliver aka Tomcat0815

I have tracked my Mustang a lot also, and switched trans fluid to Royal Purple synchromax. This worked well for track day, but when the weather got cold I had shifting issues (no additive). I then tried Redline MT fluid (also no additive) and also had shifing issues when cold. I had to double clutch to get clean shifts. I then switched back to OEM fluid and no more cold shifting issues.

So perhaps the additive would have helped? But my issues were in cold weather, normal driving. Not high RPM.

But, looking at your issue. I don't think trans fluid will help. There are plenty of threads on this forum about high RPM lockout in GT and Boss Mustangs. Solutions vary from trans bushings/ braces to Spec Stage 2 clutch kits. Oil won't help I don't think. Good luck!

Hi 5.M0NSTER,

thank you for your reply.

As I mentioned, I already got quite a few mods done and the shifting is pretty well now. I even sourced a steel braided clutch line this morning.

The german Mustang owners Club recommended a fluid change to a more modern, fully synthetic fluid to me, claiming that US fluids were not made for long time high temp situations like Autobahns or race tracks.

I guess I will just try how the new fluid works. If I get troubles, I will add the additive which I already bought.

I do not drive the car in winter anyway, I do not even have winter tires which are mandatory during winter here.

Regards

Oliver aka Tomcat0815

I am not sure that is the best fluid for that transmission, suggest you research it a bit, if you have not already done that. I think 75W-90 might be too heavy????

You guys are practically neighbors; you should meet up at a track some time . . . . that would be different, the German guy driving the American car, and the American guy driving the German car!

Glad shifting issues are getting better. Never too late to put in the additive if needed!

Bert is right, we're close to being neighbors. I live just a little north of Stuttgart. And you're in Cologne, so I'm jealous how close to Nurbergring and Spa you are :D

Nonetheless, I plan my first track day of the year at Spa in April. Still need to plan Nordshleife. What are you planning?

Oh, I just posted a rather long answer in your "moving to Germany" thread.

First, I am regularily going to "Race Park Meppen", a tiny, but fun and cheap track. I have already been there last Saturday.
Then, there are track days on an old airfield in Mendig, a little closer to you.

Also, Nordschleife about 3 to 4 times a year, but track days only. No "tourist traffic" where you can just buy a lap ticket and drive. Especially on weekends, I believe that is far to dangerous.
If you want to do public laps there, I'd recommend to go there on a weekday, maybe on a day where the track was closed to the public until 5 p.m.. They usually open the track to the public then for 1 or 2 hours, but all the crazy people (who never check the opening hours in the internet beforehand) are drunk and in their hotels by then. If you are lucky. you wont even see other cars during your laps (hint: do check whether the track is open or not if you plan to go. seriously.).

Last but not least, I might be going to Spa too in August. Unfortunately, that is rather expensive.

I should maybe add that my brother owns a tiny company running all the above events. I give him my car for the Instructors to use it for the guided laps. For that, I may participate in the open pit hours for free. I also gotta lend him a hand when changing tires, putting up banners and tents and the like.
Unfortunately, the Spa track day is not "his" event, so I would have to pay for that :-(

But I have been there in 2017 with my E46 M3 I believe and it was awesome. Totally worth it.

btw did you manage to bring your pitbull to Germany?

I am off to bed now. Good night!

If I remember correctly Ford stopped recommending the Xl-18 additive when they changed the fluid spec to the Ford QDC dual clutch fluid. I have been using the Redline MTL in mine for track use for a few years now without any additives. MTL met the original Ford spec for the MT82, but doesn't meet the revised specs. It shifts noticeably better than the stock fluid, but I don't drive my car in cold temperatures.