My Cherokee: stock, manual, 89, 222,000 miles

Hello,

So, to my understanding never changing transmission fluid in an automatic car then deciding to change it after too many miles may cause issues such as slipping. But I can't find any sort of info on if I should expect any not so good results if I do a late fluid change on my manual transmission. I'm pretty sure my tranny fluid hasn't ever been changed and my jeep is clocking in at around 222,000 miles, I'm a little late.

Has anyone had any problems with changing manual transmission fluid after far too many miles?

 

hmmm i think youre confused with an automatic transmission as manual has a clutch and if theres any slippage thats the clutch being worn out where as an auto trans is the problem when you change old fluid because its so used and old its what creates the friction in the torque converter (sorry cant figure out specifics atm) thats why im not changing mine at 210k miles, Manual is just the gears and shouldnt have issues changing it

 

Yes change it a manual transmission is different from an auto, Redline MTL or MT90 works good in the manual transmission.

Even if your jeep was an auto the AW4 auto transmission that comes in the XJs isn't like the Chrysler autos, it is still a good idea to change the fluid in a high milage automatic XJ. I changed mine 2 years ago when I had 230,000 on my AW4 and haven't had any issues yet, I am getting ready to add a bigger cooler and do a fluid flush when I do it.

 

lol for me its the fear of your only vehicle being out of commission as my trans was never opened from the factory basically

 

how exactly do you know that? When did you get the jeep?

 

If you are concerned over shocking your transmission, just drain out 1/2 gallon of tranny fluid and replace and do it every 500 miles. After the 6th time, drain completely and replace the fluid. The torque converter will always hold tranny fluid and cannot be drained unless you remove it. One more time at another 1000 miles and you should be good for 30-40k miles. Use the same brand/type of tranny fluid each time. Synthetic is also ok. Mixing with conventional won't harm anything. Merc/Dex is what the manufacturer calls for.

 

Just do it.

 

x2

Redline MT90 is great and worth the money. I use it in my 95's AX15.

 

X3 ^^^

Redline is a great product, used it in my 87.

I agree with BruceB, you could always change some and drive a little and then change some more again.

 

It's your Jeep, so if you want to change it a little at a time, that's totally your prerogative.

Folks can debate the changing of fluid in an automatic - but that's automatics. Automatics use the fluid as part of their operation in order to shift and ATF can burn. In a manual, the gear fluid is strictly lubrication - like in the differentials. New fluid will keep the gears cooler and reduce friction, so I would just go ahead and change the whole thing (a gallon of MT90 is available on Amazon for $60 and is enough for the full change) so you can get the protection right away.

The only thing to be "concerned" about with the manual fluid is that the original spec fluid was lower sulfur (GL-3) - most modern regular gear oils (GL-5) are bad for the soft metals in the synchros because thy have too much sulfur. I wouldn't put anything but the MT90 in mine, but a high quality synthetic gear oil should be safe. Just don't put in generic brand 75w-90. The MT90 is specifically formulated for our older gear-oil manuals and won't damage the soft metal components.

Edit - If you go to the Redline website for MT90 (https://www.redlineoil.com/mt-90-75w90-gl-4-gear-oil) what do they have pictured - an XJ.

 

Even in automatics, if you just change the fluid and don't FLUSH it, you're fine.

If you **** your pants, do you keep wearing them?

 

That's one hell of an answer, Thank you very much sir. That's exactly what I was looking for.

 

Anytime brother! Don't forget to get a fluid transfer pump to add it in (there's one that fits the gallon jug and works great, but a $10 pump from Harbor Freight works as well.) and make sure you can get the FILL plug open before you go loosening the DRAIN plug!

 

parents bought it brand new and never had it checked lol.

 

That's an old wive's tale, and it has nothing to do with manual transmissions anyway.

See my sig, #3.