I had my manual transmission replaced about two years ago due to the "popping out of first" problem. They put heavy gear oil in the new transmission which made it shift terribly. They finally replaced that with 5-20 engine oil which brought it back to its normal performance.

I've always been disappointed with the chunky shifting of the 6-sp so I started looking into changing the fluid to something slicker.

The owners manual says to use ATF+4 fluid. My dealer says that the current info from Chrysler is to use 5-20 engine oil.

Does any one have more information on what the correct fluid for the manual transmission is?

 

I've read on here to use 0-40w engine oil

 

The guys over on the BMW forums all recommend Red Line fluid for manuals, including M3s setup for track use. They claim it really makes a difference on the quality of the shift. I'm going to make the change soon.

http://www.redlineoil.com/products_g...p?categoryID=7

Robert

 

I lost a perfectly working transmission to Redline MTL and would never personally touch the stuff. Many others reported the same problem and every 3000gt and Stealth owner knows to stay away from that stuff. They all discovered Syncromesh was the best product for their trannys. Not to mention that MTL is WAY thicker than what we have in there. The Xfire manual calls for 5w-20 meeting API SL or GF3. I would not deviate from that until other club members experiment later on. I plan on putting in synthetic fluid meeting those specs this spring.

 

how many quarts of tranny fluid go into a manual crossfire

 

When my car spent 2 months in the shop for a "no-start" problem (caused by mother nature) , I was very fortunate to have an excellent Crossfire technician.
He changed the ATF+4 that came from the factory with synthetic motor oil. As MAXWELL pointed out, I think it was 0w40.
I had picked up 2 different kinds of "super slick" transmission additives from Summit Racing, and asked him to add it to the tranny. He told me he would if I really wanted it, but he said, there really isn't anything out there that's more slippery than synthetic motor oil. It made sence to me, so I took his advice.
I really can't say I noticed any real difference between the motor oil compared to the ATF when shifting, but it didn't get any worse either.
Service manual says the tranny takes 1.6 qts. But then the same manual also says the crankcase (with filter) takes 6.1 qts. so go figure.

 

Factory spec is for 1.9 quarts of 5W-20 engine oil. Use any good synthetic and you'll be fine.
The MB manual tranny came from the factory as a notchy shifting unit, particularly the 1st to 2nd gear throw, and no oil will dramatically improve this design flaw (ask me how I know...)

Some prior threads on this topic below:
https://www.crossfireforum.org/forum...smission+fluid

https://www.crossfireforum.org/forum...=owners+manual

 

I had my Xfire with Manual in NYC last Winter, and took it for a spin on many a cold, sub-freezing day,

The car only has about 17K miles, but it always shifted nice and smooth from 1st to 2nd, and is a non-issue thru the balance of gears.

I'm wondering if 1 & 2 are really a cold issue, or is there something else going on here...???

And yes I'm aware the extreme cold, will make things sluggish as expected, till it runs a bit, but I have yet to see it.

So the **** person I am, I moved it down to Florida for this Winter, will change the Tranny and Diff fluid around 30k miles, and continue my happy adventure with one of the most fun cars to drive (at any price)...

 

So let me get this straight. Instead of using dedicated transmission fluid with lubricants for the syncros, the 6-speed tansmission just uses regular 0W-40 synthetic motor oil?

 

I understood that the Transmission calls for Mobil 1 5w 40 100% synthetic.... and it IS a engine oil ?

Mobil only make one 5w 40 synth oil, so it's gotta be the one I guess.

GB

 

Just seems strange to use engine oil instead of gear oil, lol.

 

Agreed - a weird goo to use here, but also bear in mind I had a manual Landy Discovery that use watery ATF fluid in the main box....
and that thing weighed nearly 3 tonnes.

A Ford Capri 2.0 litre engined I had years ago used EP 90 - like thick syrup.... doubt I'd get the XF box to engage with this

I tried some other thicker fluids in another landy, and destroyed the transmission in under 1,000 miles !!!
Could barely get it into gear with the thick stuff in it.

The fact that it's a Merc box and these mechanics often survive 400,000 miles and more - I'm gonna believe the manufacturer lol

Grant B