Lucas Oil - transmission fix additive

I've read mostly good things about it on regalgs,org. A few said it prolonged the life of the trans for a year or so.

But i have no personal experience with it. But if the transmission is failing either way , can it really do that much harm?

That's what I'm trying to figure out. I read this on Hotrodders.com:

"On a fresh rebuild on a beefed AOD, the trans didn't want to shift into 2nd when cold, but shifted fine after warming up some.

A reputable local shop that I had gotten parts and tech advice from agreed with my thoughts that it was likely a sticky valve in the valve body, it had happened like that on the first rebuild several years ago.

They recommended trying an additive in an attempt to free the likely sticky valve.

I bought Lucas Oil "Transmission Fix" as it advertised it would free sticky valves and I figured it was a reputable, quality product.

I poured it in slowly with the trans fully warmed up and engine running. Was surprised how thick it was. I let it run awhile to help mix it in, then tried it.

Was dismayed to find it would hardly go in gear and, when it did, acted like it was slipping big time! Tried going from reverse to drive & back several times in an effort to work it thru the valve body and mix it in better, but no luck."

i added the stuff to my tranny almost a year ago to try and slow or fix the leak i have at the axle seal. it did the job for awhile, but eventually the leak came back. i knew it would and i plan on replacing the seal when i have it all apart for the fbody mod.

also i recommended this stuff to my dad who has a 93 park ave that leaks a ton of ATF from the main seal. it did not fix hi leak because the leak is to big, however he said the trans did feel stronger after adding it.

just wanted to note, i only added 1/2 a bottle because i didnt want to overfill my system, and seeing how thick the stuff was i didnt want to add more than was needed.
my dad on the otherhand added 2 bottles over the period of a week his buick still runs..............somehow.

I've used the stuff to good success, help my old buick lesabre out when things were on the way out. Transmission worked great till the day I junked the car with the stuff.

I started using the stuff on the reccomendation of my mechanic back in my parents neck of the woods. He's one of those old school mechanics where hes like "well shit, nevermind the bill for now, you can settle up with me if we fix the problem". Then after replacing like 10 things when the right thing is found he would only charge you for what actually fixed the problem. Anyway, he had an ancient dodge ram truck with a plow blade on it that he used to clear snow on the lot. One day the transmission just up and died, made terrible noises. He drained the ATF fluid, stuck in some of this lucas stuff, topped up the fluid, and the thing moved snow for 5 years after that. I'm not usually much for additives, but I've had very good luck with any lucas product.

saved my girlfriends neon, sigh as much as i want to see that car die it keeps going not sure why or how but it just keeps going lol

Nothing should go in your transmission except clean ATF. Whether you use Dex III or Dex IV don't add anything else.

Here's an idea. If you really want to buy this additive, put $8 in an envelope and send it to me. It will do exactly the same thing, and you won't have completely wasted your $8. I could use it.


I spent quite a few years behind the counter at a parts store/speed shop and tried a whole bunch of different things over the years, as well as talked to our customers (most of whom were regulars and race drivers). There are very very few additives that actually do anything useful.

Yes i put in all trans 2 bottles.

My $.02....

Lucas is the ONLY additive I use, regardless of what it's for.

Lube/guard is also some really good stuff. no doubt.

I just used a half bottle in my Riv for a TCC issue and while it didn't completely solve the problem, it made the slipping much less pronounced. Like mentioned before, if the transmission is on the way out anyways, it really shouldn't do any harm.