yeap on the Leatherique ...
on the Lexol, armor-all, windex, lemon something, water sprays, shoe cleaners, and the other whatevers .. nope!
leather can and will last 50+ years if done right .. avoid those or suffer the cost of recovering ...
here are the facts:
oil, petroleum, water and silicone WILL SEAL the fibers in leather and in the long run, HARDEN AND DESTROY the leather .. AVOID these like the bubonic plague ...
waterproof the leather with the proper conditioner .. YEAP!
lexol, armor-all and others are deadly to leather .. if your leather was exposed to these silcones, there are products that will remove the silicone to some degree ...
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Note that the main use of the cleaner is after the conditioner, not before as you may have read in the directions. You only need to clean heavy dirt before conditioning. A good conditioner will help loosen and lift dirt, sweat, and other stuff, making an "after: cleaning easier and more productive.
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the "Don'ts"
First, do not use anything with silicones in it. The silicones give the leather a nice finish, but do nothing to "nourish" it and will make any later repairs or recoloring very much more difficult. Armor-all & Lexol are to be avoided when it comes to leather seats or vinyl.
Second, do not use anything with water added to it or with petroleum distillates added. These also don't help the leather and may harm it.
Third, stay away from saddle soap. It does soften and clean the leather, but it is hard on the dye, leading to a premature need to recolor.
Fourth, don't leave exposed leather sitting in the sun year after year. If you must park in the sun more than occasionally, cover the leather, especially the top of the back seats. Towels are cheap. Reupholstery isn't.
harsh cleaners are not great either, but at least may leave the pores and fibers open for re-conditioning .. still, avoid them ...
best, ABSOLUTELY BEST, way to clean/condition leather:
use a mink oil+ sheep's wool fat (lanolin)+ neatfoot oil ... leather conditioners ..
YES, clean with the conditioner ...
if your car has COTTON stitching, skip the neatfoot oil ...
Leatherique contain no neetsfoot oil ...
Eagle One contains all three ...
= = = = =
the "Dos"
Use your favorite leather conditioner as often as you like, but try to do it at least once a year. Twice is better. More than about four times is overkill BUT will no do harm.
You might want to do a
light cleaning to get really cruddy stuff off the leather before conditioning. Don't feel that you need to get every molecule of dirt off, however.
Now, condition. Rub the conditioner in with your hands. Using a cloth might seem like a good idea, but you'll lose a lot of conditioner that the cloth soaks up. You want it ALL to soak into your seats. If you don't like the greasy feeling, wear gloves. If your seats are really hard, don't try to massage the stuff in as you may cause a crack. If the leather is pretty good, you can be more aggressive.
Now, park the car out in the sun for a while. Let the leather pores open and aborb the conditioner. Heat helps here. Repeat if so inclined, especially if the leather's hard.
Now, wipe any dirt residue off. Clean with a cleaner if it feels a bit sticky.
Note that the main use of the cleaner is after the conditioner, not before as you may have read in the directions. You only need to clean heavy dirt before conditioning. A good conditioner will help loosen and lift dirt, sweat, and other stuff, making an "after: cleaning eaiser and more productive.
need more from the folks that have practiced for the last 100 years?
http://www.seattlejagclub.org/restrep/
Serious dog is serious. 
