# Cub Cadet LT2042 Hydrostatic Fluid Options



## AutoWorks (Jun 14, 2021)

Hi,

I’m new to the forum. I plan to change the transmission fluid on my Cub Cadet LT2042 soon. It has the hydrostatic transmission and it calls for 6qts of CC’s drive system fluid(part#:737-3121). Is the oem fluid any different than Shell Rotella 15w40? There were a few members who swapped out the oem fluid for the Shell stuff. I don't mind spending a few extra bucks on the oem fluid, but I also don't want to spend $100 on a fluid that was re-branded. Has anyone had a negative experience with an aftermarket trans fluid?

Thanks


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## SidecarFlip (Mar 25, 2021)

Depends on what transaxle you have. If it's a Hydro Gear then 15-40 Rotella is fine. If it's a Tuff Torque then you need to use their special synthetic fluid.


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## AutoWorks (Jun 14, 2021)

SidecarFlip said:


> Depends on what transaxle you have. If it's a Hydro Gear then 15-40 Rotella is fine. If it's a Tuff Torque then you need to use their special synthetic fluid.


How do I know which one I have? I’ve searched the owners and service manual but I couldn’t find anything.


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## SidecarFlip (Mar 25, 2021)

Get under it and look at the transmission. It will be labelled either way. Hydro Gear will have a label on on the axle shaft housing. not sure where a Tuff Torque label is. If it's a Hydro gear it will also have an external spin on filter. Tuff Torque (far as I know) have an internal filter and magnet. MTD uses both btw.


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## AutoWorks (Jun 14, 2021)

It does have an external spin on filter. So, I should be safe with the Rotella 15w40 oil?


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## SidecarFlip (Mar 25, 2021)

Most likely. Be sure to get a new filter from Hydro-Gear or a dealer. Hydro Gear has a website but I get my filters from my local Kubota dealer (he sells MTD ((Cub Cadet).


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## AutoWorks (Jun 14, 2021)

SidecarFlip said:


> Most likely. Be sure to get a new filter from Hydro-Gear or a dealer. Hydro Gear has a website but I get my filters from my local Kubota dealer (he sells MTD ((Cub Cadet).


I’m probably going to pick up an oem filter. Does it matter which 15w40 I put in? There’s a T4, T5, and T6. The T5 and T6 are synthetic.


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## SidecarFlip (Mar 25, 2021)

I used T6 last time. (last year).


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## AutoWorks (Jun 14, 2021)

SidecarFlip said:


> I used T6 last time. (last year).


Thank you for your help! I’m going to pick some up at the local Walmart.


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## SidecarFlip (Mar 25, 2021)

Menards is cheaper, if you have one.


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## Bob Driver (Nov 1, 2017)

SidecarFlip said:


> Depends on what transaxle you have. If it's a Hydro Gear then 15-40 Rotella is fine. If it's a Tuff Torque then you need to use their special synthetic fluid.


Actually Hydro Gear says at least SL rated *20W50* in all of their Service Manuals. 15-40 is diesel oil and most of the stuff you'll find on the shelf today is CK-4 rated (2017 emissions). Aluminum housing, air-cooled, transaxles run way hotter than a water-cooled diesel engines. That's why you need the 50 weight on the upper end. 275 degrees is not unusual to see in a Hydro Gear unit, on a hot day, if you happen to point a laser thermometer at it.

See page #9 in the Hydro Gear Attachment below if you have any doubts about the oil
Hydro Gear Service Manual


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## SidecarFlip (Mar 25, 2021)

Been using Rotella T5 for 10 years now with no issues. What my dealer recommended as well. I'd never use 50 weight in it, period.


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## AutoWorks (Jun 14, 2021)

I found the model # after scraping a thick layer of dirt/grease off it. My machine has the BDU-10L-225 hydro model. I believe this is the service manual:https://www.hydro-gear.com/8edfe9c648_sites/hydro-gear.com/files/BLN-50327_P6.pdf

According to the manual, you use 20w50 if the air temps are between 15°F-100°F and 10w40 for temps between -5°F-100°F. I guess it's the same as the manual that was previously posted. Will the machine run significantly better with the 20w50?? Cub recommends their drive system fluid (10w40).


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## LouNY (Dec 15, 2016)

A couple of years ago I refilled my lawn mowers transmission with synthetic 20w-50, worked better then it had ever.


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## Bob Driver (Nov 1, 2017)

SidecarFlip said:


> Been using Rotella T5 for 10 years now with no issues. What my dealer recommended as well. I'd never use 50 weight in it, period.


It's your machine Bud, run what oil you want. Just thought I would share what Hydro Gear actually says in their Factory Service Manuals and teaches in their Factory O/H schools. My mistake, didn't realize you had done far more extensive reliability testing than their engineers and had a better solution. You might want to consider dropping an e-mail to their Engineering Department and tell them THEY have been wrong all this time. I'm wondering how many customer warranty claims that Dealer of yours has had rejected by Hydro Gear for recommending 15-40. They ask right on the Hydro Gear Warranty Claim Form a servicing dealer (like myself) sends in to file a claim if the end user was running *20W50.*


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## bmaverick (Feb 20, 2014)

Bob Driver said:


> It's your machine Bud, run what oil you want. Just thought I would share what Hydro Gear actually says in their Factory Service Manuals and teaches in their Factory O/H schools. My mistake, didn't realize you had done far more extensive reliability testing than their engineers and had a better solution. You might want to consider dropping an e-mail to their Engineering Department and tell them THEY have been wrong all this time. I'm wondering how many customer warranty claims that Dealer of yours has had rejected by Hydro Gear for recommending 15-40. They ask right on the Hydro Gear Warranty Claim Form a servicing dealer (like myself) sends in to file a claim if the end user was running *20W50.*


The other option (not listed in the manual), I've used with great success is Mopar ATF+4, it's full synthetic, rated for high temps, and works very well in a hydrostatic drive that requires the Cub Cadet Drive System Fluid Plus.


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## Bob Driver (Nov 1, 2017)

bmaverick said:


> The other option (not listed in the manual), I've used with great success is Mopar ATF+4, it's full synthetic, rated for high temps, and works very well in a hydrostatic drive that requires the Cub Cadet Drive System Fluid Plus.


Just for clarification, I'm a Servicing Dealer for both Briggs & Stratton and Hydro Gear. Each of their Field Service Reps stop by my shop at least once a year. Of the two, Hydro Gear is way tougher on their warranty claim process. 

"The other option (not listed in the manual)"...... There is no such thing with Hydro Gear, If it's not done exactly as stated in their Service Manuals, there is no need to even begin filing a warranty claim. If it's out of the warranty period, run whatever floats your boat


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## AutoWorks (Jun 14, 2021)

Just got off the phone with Hyrdo-gear. They recommend 20w50 for their transmission, however, they can’t recommend an oil for the gear box because they didn’t manufacture it for my machine. Being that they both share the same oil, the guy I spoke to at hydro recommended following Cub’s specifications. Why would cub recommend 15w40 if each unit was filled with 20w50 initially? Is it better for the gear box or something? Cost?


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## SidecarFlip (Mar 25, 2021)

In as much as mine is 15 years old, I don't believe the warranty is valid anyway. I'll keep using Rotella (like my dealer does) and be happy. Never had issue one other than I had to replace the 'O' rings on the charge pumps because they started leaking. No biggie other than I installed the cover backwards the first time so no go. The covers will install either way, the right way and the no go way. As an aside, I mow 4 acres so it gets a ton of use. The hour meter shows 1200 running hours. Other than adjusting the valve lash every couple years, no issues,


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## bmaverick (Feb 20, 2014)

Bob Driver said:


> Just for clarification, I'm a Servicing Dealer for both Briggs & Stratton and Hydro Gear. Each of their Field Service Reps stop by my shop at least once a year. Of the two, Hydro Gear is way tougher on their warranty claim process.
> 
> "The other option (not listed in the manual)"...... There is no such thing with Hydro Gear, If it's not done exactly as stated in their Service Manuals, there is no need to even begin filing a warranty claim. If it's out of the warranty period, run whatever floats your boat


Yes, out of warranty is the key. Cub Cadet Drive System Fluid Plus. cost about $15 or more per quart. Mopar ATF+4 costs $6 per quart, and I thought that was high. LOL 

15W40 vs. 20W50? The thicker the hotter it runs and makes the engine work harder that means burning more fuel.


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## SidecarFlip (Mar 25, 2021)

My 'boat' has been floating just fine for 10+ years now. My M60 Tank runs as good as the day I bought it. I figure the motor will give up before anything else and then it gets a Predator vertical V twin.


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