Community Forums

Birddog Pilot · 07-30-2008, 04:04 PM

There have been many interesting discussions regarding our various hydraulic systems; what powers what, where they are located and what fluids to use. Obviously WRV had a continuing progression of experiments with several types of fluids. I've been trying to compile as much information from this forum as possible to decide just what fluids I have in the reservoirs of our 2006 36' FDTS. So far the only system's fluid that is almost certain is the HWH reservoir located in its compartment behind the right front wheel. I say almost certain because I've had a bunch of hoses replaced by Cummins Cal Pacific here in El Cajon, CA; and who really knows what they might have put in when they replenished the system? There is a label in the HWH compartment wall that says ˜Serviced with Rykon Premium Oil MV." Incidentally, HWH in their technical information recommends "HWH Specialty Hydraulic Oil For HWH Leveling & Room Extension Systems." I wonder why WRV didn't use this stuff?

Now for the mystery system that supplies fluid to the brakes, HydroMax Booster and hydraulic pump for the engine radiator cooling fan – no label here. Wouldn't it have been nice for WRV to let us know what they put in their reservoirs? I suppose I could take a sample from both the HWH and rear engine compartment tanks and have an oil analysis run to see if they might be the same.

I might have missed something in these discussions, but is there a consensus about using Rykon in both systems? And if so, according to the Chevron website, there seems to be two types of Rykon Oil. One is called, "Chevron Rykon Premium Oils, ISO 15, 22, 32, 46, 68, 100." These are recommended for, "Multi-viscosity, hydraulic or circulating oil systems." The other is, Chevron Rykon Oils AW, ISO 32, 46, 68." It is listed as, "A premium quality oil, for vane and piston pumps." Chevron's specification sheets, "Applications" and "Typical Test Data" are definitely different for the two types of Rykon 46 Oils.

So, now we have two types of Rykon, one seems appropriate for the brakes, HydroMax and cooling fan pump; and the other good for vane and piston pumps. Which type are most of you out there changing to? Does anyone have an idea what WRV might have had in mind, system wise, for the changeover and use of Rykon 46? I realize that they had an issue with excessive brake pedal pressure, but then how about the care and feeding of the HWH systems?

I will throw out another discovery. When reading the Bosch "HydroMax" technical manual located in our Alpine Coach Association Technical Library I discovered that Bosch also has their opinion regarding what kind of fluid their unit likes. On page 13 it states rather specifically that, "The master cylinder uses DOT 3 brake fluid per SAE J1703, unless otherwise specified on the top of the reservoir." Of course WRV also neglected to place a placard on my reservoir. There are also a couple of cautions regarding the use of other types of fluids. One is to contact Bosch prior to using a fluid other than what they recommend. The other is about mixing incompatible fluids because of seal damage.

Wouldn't it have been nice if we all could have been furnished an operator's manual comparable in detail to what the automobile industry has been publishing for years? Then we would at least know the basics concerning what types of fluids are recommended and compatible in our Alpines. And finally, it's fortunate we have this forum as a source to share the information we need to keep our "Orphan Coaches" running.

Dick Bunting
2006 36' FDTS

Birddog Pilot · 07-30-2008, 04:04 PM

There have been many interesting discussions regarding our various hydraulic systems; what powers what, where they are located and what fluids to use. Obviously WRV had a continuing progression of experiments with several types of fluids. I've been trying to compile as much information from this forum as possible to decide just what fluids I have in the reservoirs of our 2006 36' FDTS. So far the only system's fluid that is almost certain is the HWH reservoir located in its compartment behind the right front wheel. I say almost certain because I've had a bunch of hoses replaced by Cummins Cal Pacific here in El Cajon, CA; and who really knows what they might have put in when they replenished the system? There is a label in the HWH compartment wall that says ˜Serviced with Rykon Premium Oil MV." Incidentally, HWH in their technical information recommends "HWH Specialty Hydraulic Oil For HWH Leveling & Room Extension Systems." I wonder why WRV didn't use this stuff?

Now for the mystery system that supplies fluid to the brakes, HydroMax Booster and hydraulic pump for the engine radiator cooling fan – no label here. Wouldn't it have been nice for WRV to let us know what they put in their reservoirs? I suppose I could take a sample from both the HWH and rear engine compartment tanks and have an oil analysis run to see if they might be the same.

I might have missed something in these discussions, but is there a consensus about using Rykon in both systems? And if so, according to the Chevron website, there seems to be two types of Rykon Oil. One is called, "Chevron Rykon Premium Oils, ISO 15, 22, 32, 46, 68, 100." These are recommended for, "Multi-viscosity, hydraulic or circulating oil systems." The other is, Chevron Rykon Oils AW, ISO 32, 46, 68." It is listed as, "A premium quality oil, for vane and piston pumps." Chevron's specification sheets, "Applications" and "Typical Test Data" are definitely different for the two types of Rykon 46 Oils.

So, now we have two types of Rykon, one seems appropriate for the brakes, HydroMax and cooling fan pump; and the other good for vane and piston pumps. Which type are most of you out there changing to? Does anyone have an idea what WRV might have had in mind, system wise, for the changeover and use of Rykon 46? I realize that they had an issue with excessive brake pedal pressure, but then how about the care and feeding of the HWH systems?

I will throw out another discovery. When reading the Bosch "HydroMax" technical manual located in our Alpine Coach Association Technical Library I discovered that Bosch also has their opinion regarding what kind of fluid their unit likes. On page 13 it states rather specifically that, "The master cylinder uses DOT 3 brake fluid per SAE J1703, unless otherwise specified on the top of the reservoir." Of course WRV also neglected to place a placard on my reservoir. There are also a couple of cautions regarding the use of other types of fluids. One is to contact Bosch prior to using a fluid other than what they recommend. The other is about mixing incompatible fluids because of seal damage.

Wouldn't it have been nice if we all could have been furnished an operator's manual comparable in detail to what the automobile industry has been publishing for years? Then we would at least know the basics concerning what types of fluids are recommended and compatible in our Alpines. And finally, it's fortunate we have this forum as a source to share the information we need to keep our "Orphan Coaches" running.

Dick Bunting
2006 36' FDTS

Wil Rathke · 07-30-2008, 04:48 PM

In the Scheduled Maintenance section of the owners manual that came with my coach, the type of fluid to use in the listed for most of the service.

Algoma · 07-30-2008, 04:57 PM

It really would have been nice if they had provided this information in the manual. But we are where we are with no one to yell at.
In my 6 months of ownership I have come to the following conclusions with my '98.
The HWH hydraulic system uses its own fluid. This is basically Dexron 3 without the color additive.
The master brake reservoir uses DOT 3 brake fluid.
The hydraulic reservoir in the engine bay that feeds everything else uses Dexron 3. As far as I can tell this is where all the issues are with the later coaches. Luckily my brakes seem OK so I won't be experimenting with all those different grades of Rykon. Good luck with that one.

OldForester · 07-31-2008, 06:37 PM

Dick,

Since we both have 2006 coaches, I thought I would share my experience with hydraulic fluids with you. Fortunately we have a few more labels on ours. We also have 30,000 miles on our coach; don't know how many you have.

When we had all the hydraulic hose failures -- 4 sets -- on the master slide, and our hydraulic reservoir said used Chevron Rykon hydraulic fluid, WRV technical (Mike Glazier) and HWH technical department (can't remember name) said it's ok to substitute Dexron 3 Transmission / Hydraulic fluid. We lost so much fluid with those issues and weren't all that convenient to Chevron at the time, that we did exactly that. 1 1/2 years and 20,000 miles later, it has worked just fine. So I wouldn't worry about making that substitution for the HWH hydraulic reservoir.

For the brake / hydraulic radiator cooling fan / power steering system, our reservoir is labeled to use Valvoline 15-40 engine oil, just like the engine. We have replaced the filters in that reservoir and used the same oil, and it has worked just fine. There have been threads on the forum about people switching this to Rykon and having brakes that were easier to apply. In our '06, brake pedal pressure to stop the coach is not an issue, so we just continue with the label on the cannister and replace the fluid with the Valvoline oil.

Hope that helps-- I woudn't get too stressed out about the fluids, just use what we do and make sure the fluid is clean and topped up, and the filters in the brake reservoir changed periodically - every 20,000 to 30,000 miles or so, depending on how much you use the brakes.

Birddog Pilot · 08-03-2008, 03:43 PM

My sincere thanks to all who responded to my subject on the use of Rykon and other oils. I try not to get too "wrapped around the axle" when it comes to specific details, but sometimes my curiosity gets the better of me. What I really didn't want to do, without the aid of placards designating what fluids are currently in the various hydraulic systems; was to mix fluids that are incompatible.

A big thanks to "OldForester," a fellow 2006 owner, for your kind words of wisdom. I too feel that the current braking capability, with whatever type of hydraulic fluid or motor oil being used, is probably producing adequate braking. I only have 7600 miles on the Alpine; unfortunately it has spent a lot of maintenance time at Junction City, three plus months, and another five at various facilities here in San Diego. I'll wait a bit longer, until enough miles or when a few more months roll around, to make the decision as to what type of fluid the brake, hydraulic fan/pump and HydroMax will be either serviced with or changed to. Hopefully by then the jury should be in regarding the pros and cons of Rykon vs. motor oil.

Dick Bunting
2006, 36' FDTS