Substitutes for Berryman's B-12 in transmissions

A few days ago I submitted a question about my transmission failing (1994 Oldsmobile Cutlass Ciera V6 with automatic transmission) and received replies from transman and another party to use an additive from the Berryman’s B-12 line of products. I presumed that I could go to a local auto parts store and find the appropriate product. I found a few Berryman B-12 products, but not one specifically for transmissions. So I contacted the company and their reply was that they had discontinued their transmission products 6 years ago. They do not recommend using any of their other products in a car’s transmission due to a likelihood that the products would damage the seals. So I need clarification as to what specific Berryman’s B-12 product my responders had in mind, and whether there may be other similar products that I could use from other companies.

Nobody has responded to this, so I’ll bump it up in case Transman shows up.

I do not know the symptoms but if a fluid and filter change fixes it that is better than an additive. How many miles since any transmission service?

The Berryman B-12 that is recommended is actually not a transmission product at all.
It’s the red/white/blue can marked as carburetor cleaner and/or fuel injector cleaner and yes, I’m aware that technically this product should not be used in transmissions.

It’s what I’ve used for 30 years; when the particular need for it arises that is.

In transmissions???

Yes, in transmissions.

This came up a couple times in the past couple of years, and I also asked Transman to verify it, and he did.

If Transman says yes, then I’m willing to believe its capable of providing the results he says it does for the symptoms he recommends it for.


Yes - the carb/fuel injector cleaner is always what both ok4450 and transman have attested to using with success. In fact I didn’t think Berryman’s ever even made anything they labeled for transmissions.

On that red, white and blue can you will see the words “In the gas, in the oil” I learned about it many years ago from an old transmission guy. Been using it for many years with much success. It softens the piston seals and keeps the trans/valve body clean. I used it in my own transmission for several months when the front clutch seals hardened up and I was getting a delay from 2nd to 3rd and in reverse engagement. One can in the trans straightened it up for a good 30-40 days before I had to use another. I did this for probably a good 7 or 8 months. (Was so jammed up with work I couldnt get to my own trans). When I tore it down with over 150k on it, it was immaculate inside and the seals felt new. B-12 is just a band aid. The cure is to rebuild.




Transman618 Can I ask why you don’t like Lucas? I have had good luck using Lucas.

makes sense

The package has been changed sometime recently and no longer says “in the gas, in the oil” anywhere on the can. This had me leery of using it in my transmission recently, but I did so on the advice I have seen over the years by transman and ok4450 over the years. I used it in a Jeep that had a slight slip first thing in the morning in colder weather, and the slip is gone.

There’s a product called Seafoam TransTune that’s formulated to help clean gum and varnish from transmission valve bodies that might cause shifting problems. It doesn’t stop leaks nor does it modify the transmission fluid. And if this stuff doesn’t work, then the transmission likely needs to be repaired or replaced.


Thank you all for your suggestions.

Yes, the last resort is to use the fuel treatment in the transmission. Read the label and check the ingredients. If you happen to have some of any of them on hand you can try your own cure. The Berrymans B-12 costs very little anyway, so why bother experimenting?

Trans-Medic, Trans-X and Sea-Foam Trans Tune seem to be similar and interchangeable. They more often than not greatly improve shifting and eliminate chatter and dragging from the lock up clutch.Possibly the B-12 has the same or very similar ingredients Of course, once the clutches have become paste in the bottom of the pan transman or his friends will be the only alternative. My transmission shop owner friend always said if everyone kept their transmissions serviced regularly he would be forced to get a job.Most transmission failures are directly related to lack of maintenance and abuse.

B-12 is less than 3 bucks a can around here. SeaFoam is about 9 and everything else even higher. The 3 dollar stuff works just as well as the 9 and up so that’s why I use it.