Lucas Transmission Fix, Valvoline Stop Leak -safe?

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My 15-year-old Dodge car has a major transmission leak. The dealer said would cost $2000 to fix, or $3000 to buy new. I purchased Lucas Oil Stop Slip which is supposed to plug trans leaks. Also Valvoline Transmission Stop Leak.

Are these things safe to use, or am I better-off to just keep adding a quart of trans-oil every week? (The leaky transmission runs perfectly. No slips or grinding.) Since it's "rusting out" underneath, I decided to just keep driving as is until the car stops moving.
 
I've used the Lucas in the past on a few different vehicles (mostly college friends) to no ill effect. It did make the clunky transmission shift smoother and slowed down the leak a bit.

Basically, the stuff is as thick as molasses and very tacky. If you have a serious leak I doubt it will stop your leak completely but might slow it down. If it's a beater car, I wouldn't be afraid to try it.

The most important thing is to keep the fluid topped off. I would use the cheapest ATF +4 you can find (most Chryslers use this), which will probably be the Wal-Mart Supertech.
 
Dont do it.Lucas will alter the friction coefficient of the fluid and you will get torque converter clutch shudder and eventual failure.Chrysler is very specific about not using additives in with ATF+3/4. 15 years old,so its a 1998 Neon/Stratus/Avenger/Intrepid? (you dont have a Dodge in your signature).With the exception of the NEON,its probably the good ole 41TE.Thats not a trans to mess with.
Where is the leak? Torque converter seal?Solenoid pack? Output seals?
 
Those types of things really are made for just getting by a few more days. If you choose to put them in your car realize they will probably finish it off. Those additives thicken the fluid significantly and affect pressures in the tranny. If the tranny is electronically controlled it can freak out the computer because it will not understand what is wrong and shift incorrectly. Seen that personally. On the other hand if you keep topping off the tranny you are doing no damage and as long as you keep topping it off you will keep going. Have you considered giving Maxlife a try? not sure if they make a Maxlife specifically for ATF+4 applications or not. I personally would stay away from additives like that unless you are sure that the car will be done in a week. From my experience there is no fix like the correct fix. Adding fluid once a week is way cheaper than not having the car or replacing the tranny next week. If you are ready to part with it them dump that stuff in and see what happens. I would not do it in my beater.
 
What would MaxLife ATF+4 do different than the Chrysler ATF4?
Originally Posted By: NHGUY
Dont do it.Lucas will alter the friction coefficient of the fluid and you will get torque converter clutch shudder and eventual failure.
OK. I'll take the Stop Leak back to pep boys.

One dealer told me the Avenger needs a new transmission pump. A second dealer said both pump and torque converter. Both said they'll probably find more problems once they take it apart. So I decided not to bother.


BTW I used Red Line C+ ATF in this car. Apparently that was a mistake, even though they claim it's good for ATF+4 and +3 cars
 
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I'd consider getting a second price quote/opinion from a well-regarded independent shop.

In my experience dealer prices are quite high. I lived in Irvine about 6 years ago and while I don't remember a place off-hand (and my cars are Japanese), it should be relatively easy to find something. I'd check Yelp first. It's far from perfect, but if a place has lots of good reviews it's a start. Might also try areas around Irvine like Tustin, Costa Mesa, etc...places where shop space/prices are likely to be less.

If you feel industrious, posting and asking for a recommendation on a Dodge forum with a lot of users might also yield fruit.

Might be worth the effort. I've had a dealer quote expensive (and un-necessary) work before.
 
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If the lucas product is their AT conditioner, I'd use it. I have used it before on a 93 Grand Cherokee. Stopped the leak and improved performance. Sold it a couple of years later just fine.

I have a conditioner that I sell and use. Put it in my BMW about 8 years ago and it cleaned up the governor and stopped the leaks. Started shifting fine instead of taking miles to get through the shifts. I didn't put any in when I did an oil change a few years later, and 3 months ago it started shifting problems again. One bottle and it is like new again.

It is just a diluted ester that acts as a seal softener and cleaner.
 
The local shop told me $3000. I said that's how much it costs for a whole new one. He said, "Yes because it appears to have major leak and needs new parts."

The allpar forum said that quote is likely accurate, and I should either junk the car or bite the bullet and fix it. (In the future all my cars will be cheap easy-to-fix manuals, not automatics or CVTs. Better MPG too.)
 
Originally Posted By: widman
I have a conditioner that I sell and use. Put it in my BMW about 8 years ago..... I didn't put any in when I did an oil change a few years later, and 3 months ago it started shifting problems again. One bottle and it is like new again.
What's it called?
I have Lucas Stop Slip which has a sticker on top that says "Also stops leaks". Plus the Valvoline Stop Leak for transmissions.
 
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Okay well I decided not to pour this stuff into my transmission. I'm afraid the Lucas stop leak might turn the seals to mush & make the problem worse. (On amazon one customer complained it only extended his trans' lifetime three months and then it died.)
 
my 09 taurus began having a tranny fluid leak. i noticed it in the driveway and it's leaking slowly but still leaking as we speeak. it began a few days ago. should i add about a quart and take it to a mechanic or transmission shop? i jacked it up and saw the leak was coming from the transmission pan. what was the cause of this and how can i fix it and how much will it be roughly?
 
Originally Posted By: RandomIn707
I'd consider getting a second price quote/opinion from a well-regarded independent shop.

In my experience dealer prices are quite high. I lived in Irvine about 6 years ago and while I don't remember a place off-hand (and my cars are Japanese), it should be relatively easy to find something. I'd check Yelp first. It's far from perfect, but if a place has lots of good reviews it's a start. Might also try areas around Irvine like Tustin, Costa Mesa, etc...places where shop space/prices are likely to be less.

If you feel industrious, posting and asking for a recommendation on a Dodge forum with a lot of users might also yield fruit.

Might be worth the effort. I've had a dealer quote expensive (and un-necessary) work before.

+1. Check out a couple of independent shops.
 
Is your ATF level full? Was it ever serviced? miles?

The Lucas will mix fine with the ATF+4 and simply thicken the fluid and mildly condition the seals. It won't fix missing/blown seals/gaskets...

Maxlife transmission stop leak is used at a 1:10 ratio as a top off or substitute for the OE fluid. Its is an ATF. At the 1 quart to 10 quart ratio, it shouldn't dilute the ATF+4 friction modifiers much.

If it continues leaking after the LucasTransmissionFix and/or the Maxlife StopLeak, just keep topping it off with ATF+4. Eventually the leak will either start a fire, or it'll run empty.
 
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