Lucas Trans fix?

[A1218]

I’ve heard quite a few people using Lucas trans fix in a rougher shifting older transmission and some even using a half bottle or so during fluid change as preventative maintenance. Some being Pathfinder, frontier or Q owners.

Is this stuff okay or safe to use in a functioning transmission like my 1997 Nissan Pathfinder with 191k miles? Not that I’m having problems.

I used Castrol high mileage transmission fluid in a drain and fill about 1.5 year ago. Last month did another drain and fill with Royal Purple Max High Performance Synthetic ATF.

[mdmellott]

My neighbor highly recommended it to me several years ago, as a preventative maintenance additive. I had about 200k miles on mine at the time and never thought I had any slipping issues, just a bit of a harsh engagement shifting from P to D or R. Figured to couldn't hurt to try and I was impressed with it when I did. Shifting became smoother and I realized a slight improvement in acceleration from a standstill, as an improvement was made to diminish slippage as well, which I never thought was an issue in the first place. I wish I could explain the fluid engineering behind this but I trust the good reputation Lucas Oil has. I think it's a fine band-aid on older transmissions with issues and a good preventative maintenance additive as well. Still going strong at 225k miles.

[A1218]

Yeah I was thinking of trying it out and I don’t think it would hurt anything as well.

Did you use the whole bottle?

The direction state that you can add to existing fluid without draining but I think I’ll suck a half quart out before adding.

[QX4ME]

Well, after reading the post I think I am going to try it too. Mine has got 120k miles with no issues.

By the way, I used Lucas engine fix about a year ago as I noticed engine oil slow leak. It took longer than most online people said like a few days of driving to stop the leak. I noticed after several weeks later the leak stopped, or very slow leak I don't bother checking.

[mdmellott]

Did you use the whole bottle?
The direction state that you can add to existing fluid without draining...

I used the whole bottle. The directions gave be pause as well, to think an overfilled transmission is not what I want. I drained a bit before adding it. It's kind of thick so if you warm up the bottle of Lucas in the Sun, or put it in a pan of hot water for awhile, that will help getting it poured down that skinny transmission fill tube.

[mdmellott]

It took longer than most online people said like a few days of driving to stop the leak. I noticed after several weeks later the leak stopped, or very slow leak I don't bother checking.

A good seal rejuvenating additive takes awhile to work its magic. A couple hundred miles of driving, before it takes effect, would be normal.

The Lucas Transmission Fix does its thing almost immediately.
It won't fix worn out badly slipping transmission bands but it will add more life to their operation, minimizing slip as much as it can, and give a longer life if they are just worn with age but not worn out.