adding tranny additive like Slick 50 or Lube Guard during AFT change?

[632 Regal]

I dont believe any additives are helpful, maybe in a last ditch attempt to make it to a trans shop without getting a tow truck but definetly not in a new transmission or a rebuilt one.

[peterllo]

I just replaced the trans in my '95. The shop I use uses a Wynn's additive, makes the fluid very slick. My b-in-law also uses an additive. The additives in their opinion do not extend the maintenance interval as much as reduce wear.

Prior to my rebuild I serviced and flushed the trans twice (through the shop) and was able to squeak an extra 20k out of it.

[granit_silber]

I have posted about his problem and received lots of help but this question if about the solution offered - change the tranny fluid & filter.

It's a 1990 525i with 245K miles with a replaced tranny 10K miles ago with a used one form a junk yard.

The problem it's having is slipping during shifting between the low gears.

When I change the ATF does it makes sense to add something like Slick 50 or Lube Guard?

If so, which do you recommend and why?

Many thanks!

Was the tranny from the junkyard rebuilt before it was installed? Do you still have the tranny it replaced? If so, have it rebuilt and installed, then no slipping.
-ashley

[John B.]

I've read nothing but good things about the Lubegard additive & will be adding it when I refill after changing the filter in the 95 525iT next weekend. According to their website (http://www.lubegard.com/automotive/trans_atf.html) it's recommended by BMW and other Euro mfgrs. A friend of mine that has run an independant BMW repair shop for many years swears by the stuff.

[BillionPa]

slick50/duralube = bad bad bad!

lubeguard has mixed reviews with no clear position, the only 2 additives which seem to be the real deal for transmissions are LubeControl LC20 and Auto-RX.

the ARX would be for BAD transmissions, and the LC20 added as an antioxidant to standard trans fluid.

of course, if your transmission is clean and working properly, than the best option is to use high performance synthetic fluid like Redline D4 and not use any additives at all.

[John B.]

I wouldn't use any Slick 50 products myself but I've yet to read or hear anything bad about the Lubegard tranny additive. If you have any real info post it.