98 Jeep 4 x 4 Grand Cherokee Laredo transmission leak

When is the transmission leak serious enough to get it repaired? Is adding 1 quart per month not too serious? Do the transmission leak additives help and are they trust worthy? If so which one do I buy? The dealer says no to the transmission leak additives. Any thoughts anyone?

JMHO, a quart per month is serious. If the leak is not repaired at least check and fill the transmission on a regular basis; maybe a very regular basis as time goes on because things can go downhill very quickly.

An additive to help soften and swell seals may help to stop or at least slow down a leak. It will hurt nothing.
The caveat would be that an additive may not have an affect on all leaks. It depends on why a seal is leaking or if the leak is related to something that an additive will not have an affect on such as a pan gasket, etc.

The transmission leaks after I drive it, but if it just sits it does not leak much at all. Does that information help with the diagnosis. When you say goes down hill fast what does that mean. This leaking has been going on for a long time with it gradually getting worse. It has gradually gotten worse over the last 12 months. I get different information from different mechanics. Should I start with the additive or not per the dealer?

check to see if its the pan gasket…thats a cheap easy fix

By going downhill fast, I mean that an automatic transmission that is low on fluid can be damaged in a very short amount of time.

I would try to get several more opinions on the source of the leak. Check with a local independent transmssion shop and avoid the chain stores such as AAMCO, Cottman’s etc.

While it’s not always true, if the transmission is only leaking when the vehicle is running then that can often point to a problem with a fluid cooler line, torque converter seal, etc.

The worst case scenario on a transmission leak is the torque converter seal; also known as a front pump seal.
These seals are about 10 dollars, give or take, but the transmission must be removed to change that seal.
Any other leaks are generally ones that are comparatively easy to resolve.