Small Hydrostatic Transaxle Leak

[Spec_tech]

Hey Everyone. I've got a LT1045 Cubbie that i just found has a small Transaxle leak after leaving it over the winter.
It looks like it's right where the two halves of the housing meet, and that it has some crappy SVT silicone gasket maker as the gasket.

I read in the service manual that the transaxle is supposed to be sealed and maintenance free, so it sounds like someone pulled it apart and put it back together badly before me.
So i ultimately have two questions.

The first question is, does this mean that the transaxle is going to have to be taken out, pulled apart, and resealed? Or is there an easier way to take care of this? Like just adding more fluid in when needed or adding some sealer to the outside.

The second question is, the service manual notes that the transaxle fluid that's needed is 20W-50 motor oil with an API classification of SH/CD. I'm not exactly sure what the SH/CD classification means. Will any regular 20W-50 motor oil work? Or does it have to be specifically labeled "hydrostatic" fluid, like i've seen, for 20W-50? I'm not seeing any info about the SH/CD classification on any of the fluid i'm looking up.

 

[StarTech]

To be done properly it has to come out.

As the API classification of SH/CD, they are obsolete oil classes. But yes it is the same motor oil as vehicles use.

The American Petroleum Institute, API, is a U.S.A trade association for the oil and natural gas industry. It reunites different actors in the production, refinement, distribution and many other activities around petroleum. Amongst their activities, they set up diverse technical standards, such as measurement methods, standards for the design of pressure vessels, etc., but also industry standard for the energy conservation of the motor oil.There are two categories: gasoline and diesel. Category S is for “Spark Ignition”, for Gasoline and category C is for “Compression Ignition’, for Diesel. For both, the letter S or C is followed by another letter. For example, SM or CF. The higher the letter, the more recent the technology of the oil. For recent oil, the higher specification will supersede the lower letter grade. For example, if we have an oil with specification SN, it can also be used for vehicles which request API SM, SL and SJ; it is backward compatible.

However, you have to pay attention to the year of construction of the engine. If the engine is too old, modern chemistry might not be adapted or compatible with old engine designs and materials used to make the engine. Let’s see by category how it works.

Below are all the API categories in Gasoline. It
is mainly for passenger car, as most of the cars in US are Gasoline and not
Diesel.

Specifications from SA to SH are considered obsolete, meaning that you cannot get any official license from the API. It is meant for 1995 and older engines. As explained earlier, the higher the letter, the more recent and a higher specification would supersede the lower ones. API SN to SJ are for the most recent cars, API SH to SA for the older cars. Few examples to illustrate what would be the best:

- Example 1: Car from 1987 and you only have two available oils, one with API SH, the other one with SL. If you read the table properly, the car needs an API SF. In theory, both SH and SL could be used. As also explained earlier, more modern oils are not necessarily adapted for older engines. Therefore, the oil with SH level would be more adapted.

- Example 2: Car from 2003 and you have different oils available: API SJ, SM or SN. In this case, you need API SL, so an API SJ, lower, cannot be good. SM and SN supersedes SL so both oils can be used.

 

[Spec_tech]

@StarTech Awesome. That's all great and informative stuff. Thanks for that explanation.
Sounds like any modern 20W-50 oil will do. Just gonna go grab some from a local auto parts store here soon.

I was kind of hesitant to take the transaxle housing out, but I don't have anything to lose except time until the grass needs to be mowed