Contour Enthusiasts Group Archives Forums Modifications Transaxle ATF+4

Another possible MTX fluid. Chrysler spec ATF+4 is finally available without the Mopar label. Read that "now available from other places than the dealership".

You may remember that I started suggesting ATF+3 several years ago. It is still an auto trans fluid, but it has a higher level of friction modifier to start with than Mercon so no additional friction modifier is needed for smooth shifting on our MTX-75. I did some research with my oil supplier (at the time, a Castrol distributor) and he inquired of Castrol. The response was to the effect of try it and see, it should be fine, Chrysler uses it on many of their manual transmissions.

I tried it and used it for years with excellent results. Eventually I tried Ford Honey with added friction modifier. The Ford Honey with added friction modifier works marginally better.

ATF+4 replaces ATF+3 in Chrysler applications. What has never been clear is if it was a synthetic blend or if it was full synthetic. As you can see from the picture on this link the Valvoline version (and maybe others) is full synthetic. I'll be trying it on my next trans fluid change.

http://theoildrop.server101.com/ubb/ultimatebb.php?ubb=get_topic;f=16;t=002789

Yeah I guess Chrysler finally released the patent. We got two cases in today. I will be using it as a break-in fluid when my trans is done.
-tropictour

Well I remember Demon using ATF+3 as a break-in fluid, and the ATF+4 supercedes the 3. So....
-tropictour

So would being full syn be the disadvantage or the price? Should only a conventional be used for break-in?
-tropictour

Only the price would be a disadvantage. ATF+3 is about half the price and should work as well for break-in.

....break in 'bunk'.A new factory MTX75 comes in the
car with factory fill honey,what BS to apply the same
logic to a break in of the trans as an engine!,FWIW
many new cars come with synth in the engine from the
factory...all this break in ,no synth etc is old wives
bunk!!!!Why would you impregnate things like new
blockers etc with an ATF that is no longer spec for an
MTX....downright dumb!

I guess that I should have added that I don't feel that break in is needed, but if you do, use a quality oil without it being the most costly. Many seem to think that there is a need for break in is needed with a Torsen. I don't know, I have not invesitgated it.

It may be true that Ford Honey is current factory spec for the MTX-75 but I'm not convinced that it is the only appropriate fluid. Sorry, but I don't worship at the alter of Ford Engineering. I'm also convinced that I will stay away from Red Line MTL since it has shown to be questionable.

Lets not go down the road of that "everlasting" thread again about which is best. There are many that should work great. Red Line is very questionable. There have been no complaints about many others, such as Royal Purple, Pennzoil, Torco, and Specialty Formulations.

I know Jim, that is not the direction I intended the thread to go. I'll just contact TH directly and see which he recommends. Thanks.
-tropictour