What is the best gasket maker for transmission pan?
3M High Temp Silicone Gasket sealer can be used on intake manifolds, oil and transmission pans, timing chain covers, thermostat housings, and valve covers. It is easy to use by simply applying it to a clean and prepped surface area, and you can start the engine 15 minutes after application.
Permatex Automatic Transmission RTV Sealant is specially designed to withstand the harsh detergents and friction modifiers found in automatic transmission fluid that break down normal RTV silicones.
Apply RTV only to the areas that need it – don't put it on the entire gasket. Remember that when the casting/gasket is torqued into place, the RTV will flow into the joint and gasket. Some manufacturers will recommend the amount of RTV to be applied, and it's good to remember that a little RTV goes a long way.
Permatex Automatic Transmission RTV Gasket Maker is a specialty gasket maker that offers improved transmission oil resistance and good adhesion while retaining flexibility. It is sensor safe, non-corrosive and can be used as a gasket maker or dressing.
Silicone Rubber Adhesive Sealant uses only a bead of sealant to make the seal between transmission and pan. Although original equipment manufacturers use silicone sealant in these applications, most gasket types will work with these style pans as they are of the flat surface type.
Shaft seals for all types of transmissions
Transmission shaft seals are used for the input and output shafts of all types of drive-line units including transmissions, transfer cases, Rear Drive Modules, Power Transfer Units as well as hybrid and e-Drive units.
All you'll need to do is purchase a new gasket (which is relatively inexpensive). Also, make sure the bolts in the pan are tightened enough. If they're not, this could result in a leak. Many times the pan isn't secured properly after a transmission fluid change, causing a transmission leak to occur.
There are a lot of things that you must do with your rubber gaskets to keep them functioning properly for long periods of time. Arguably, the most important thing your gaskets need is rubber gasket coating. However, they also need sealant.
Typically, gasket sealers aren't really needed for transmission pans. The pan gasket itself should be sufficient enough to seal the pan from leaking transmission fluid. However, if the mating surface has been reshaped, a gasket sealer may help.
You're not supposed to use sealant, just GASKET, nothing else. I'm telling you this, because of the hundred or so trannies I've rebuilt, more than half, had been damaged by people not using silicone properly. So use only gasket material specified for transmission fluid.
Is RTV better than silicone?
Performance Of 100% RTV vs.
Pure silicone will have stronger adhesion, less shrinkage lower temperature application, and stronger resistance to weathering. If you are using your silicone in an oven or on a rooftop in Florida, 100% RTV will handle the heat much better.
Stop leak products can cause irreparable damage to your vehicle. If you notice a red, brown, or black stain on the driveway underneath your vehicle's transmission, you could have a nasty leak forming right before your very eyes.

The pan gasket is rubber. The recommendation is apply grease to the pan under the gasket. This is supposed to hold the gasket in place. Usually it does, although the process always makes me nervous about the gasket moving and causing a leak.
Transmission gaskets are usually replaced once every 30,000 to 100,000 miles. Replacing the pan gasket is usually part of the transmission service that should be done at the interval suggested by the vehicle manufacturer. Some newer vehicles with automatic transmissions have a “sealed-for-life” transmission.
Bar's Leaks Transmission Stop Leak starts working the minute you install and start driving the vehicle. You will usually see results in about 200 miles or three (3) days of driving.
Thankfully, this particular problem does not require a major repair. Your technician can repair the transmission leak by replacing the seals to fix the problem.
All you'll need to do is purchase a new gasket (which is relatively inexpensive). Also, make sure the bolts in the pan are tightened enough. If they're not, this could result in a leak. Many times the pan isn't secured properly after a transmission fluid change, causing a transmission leak to occur.
For the purposes of this article, we will focus on just three common rubber types found in O-rings and similar automotive seals: Buna N, Viton, and EPDM. Note that each type is actually a family of rubber compounds.
Transmission gaskets are usually replaced once every 30,000 to 100,000 miles. Replacing the pan gasket is usually part of the transmission service that should be done at the interval suggested by the vehicle manufacturer. Some newer vehicles with automatic transmissions have a “sealed-for-life” transmission.
Many people think that using stop leak products can save money by stopping a transmission fluid leak. Unfortunately after affects of using leakage stopping products come at a significant cost. Stop leak products can cause irreparable damage to your vehicle.
How do you get a transmission gasket to stay in?
The pan gasket is rubber. The recommendation is apply grease to the pan under the gasket. This is supposed to hold the gasket in place. Usually it does, although the process always makes me nervous about the gasket moving and causing a leak.