Power Steering Fluid

[bldski]

I have tried to search this forum with no success.

So here goes, I have tried to find the correct power steering fluid for by Tiffin 45OPP but no success.
It would be great if someone on this forum could provide me with the correct fluid.

[DAJO]

Most reservoirs have the fluid type written on them.

[ekim]

Dexron III is what my 2018 says. Of course that spec doesn't exist. It would be nice if Tiffin would provide a current spec to go by or specific brands/blends to use.

[SafariBen]

Anything that's compatible with Dexron III, or transynd would be ideal. Any synthetic ATF would be better than Dexron.



Some power steering tried 46 weight hydraulic oil, that didn't work so well in the cold. If your fluid is clear, not red, change it to synthetic ATF.

[zombiewoof]

I am in the midst of flushing and changing my power steering fluid on my 2021 Bus. It requires Dexron III. This is what I am using.

[ekim]

Originally Posted by ekim

Dexron III is what my 2018 says. Of course that spec doesn't exist. It would be nice if Tiffin would provide a current spec to go by or specific brands/blends to use.

I just discovered that TES-389 is supposed to be the same as DEX III. I would go for transmission fluid that **meets** TES-389 spec. That might be as close to DEX III that you can get with an active spec.

I suspect that TES-295 is also good, but I can't find a reference that says TES-295 meets the TES-389 spec. I don't know if there's something about the PS system that would care about any difference.

--- Found ref from the engineer that wrote the spec - 295 can be used where DEX III is specified:

Talking about 295:

Originally Posted by hzjcm8

Absolutely. TranSynd had a valid GM DEXRON-III license at one time. The GM DEXRON-III specification is obsolete now so you can only buy non-licensed "D3M" fluids. These fluids are not licensed by either GM or Ford; so, I don't recommend them. The "D3M" means DEXRON-III/MERCON and is supposed to represent that these fluids are formulated to meet both specs. However, neither Ford nor GM license these products and that's why they cannot use those trademarks (i.e.: DEXRON/MERCON).

I suspect Tiffin and Bay Diesel don't use TES-389 fluids and the power steering systems seem happy enough :-).

[garykk]

Dexron Vl is compatible with Dexron lll.

[Shawn Cole]

Originally Posted by bldski

I have tried to search this forum with no success.

So here goes, I have tried to find the correct power steering fluid for by Tiffin 45OPP but no success.
It would be great if someone on this forum could provide me with the correct fluid.

bldski, I confirmed with our mechanic shop this morning that they in fact use Dextron III just as other have mentioned in this thread.

[ekim]

Originally Posted by Shawn Cole

bldski, I confirmed with our mechanic shop this morning that they in fact use Dextron III just as other have mentioned in this thread.

Problem Dexron III is obsolete. This means that someone can say - use my stuff where you would typically use Dexron III. BUT that product may or may not have the same formulation required to meet the Dexron III spec. Those "small changes" may or may not have a negative impact our use for power steering.

You cannot get a product that says what's needed: "Meets or exceeds the requirements for Dexrom III". This is much different than : "Use where Dexron III is called for".

PLEASE - reach out to the steering gear manufacturer (ZF?) and let us know what **current** spec they require. Maybe specific **easy to find** products.

By way of example Dex VI is commonly thought of to be comparable with Dex III, However GM specifically states that it **NOT** a replacement in power steering applications:

[ekim]

I walked over the chassis department and they gave me the steering gear part number - Tiffin part number as 5007575 but they have no info on the ZF part number.

Tiffin also said - just get any ATF that says dex/Merc or dex III on it. In the chassis shop they use NAPA Dex Merc. In the store they have on the shelf MaxLife Multi-Vehicle Full Synthetic ATF - not sure if what they would sell for steering gear.

The manager there said to Dex VI would be fine. I told him about the writing on the table that said - not for power steering gears. He was unaware and basically said use any ATF you are comfortable with. That's why I was there in the first place :-(

There was no parts guy in the store and after waiting for 30 min for someone to show up I left.

I called ZF and asked them about the steering gear. They didn't seem to be able to figure anything out from the steering assembly I gave them (RL77EM) [EDIT]RL-80 is what's on the plate.

A lot of effort just to get the answer to a simple question.

[shepardmike]

Originally Posted by ekim

I just discovered that TES-389 is supposed to be the same as DEX III. I would go for transmission fluid that **meets** TES-389 spec. That might be as close to DEX III that you can get with an active spec.

I suspect that TES-295 is also good, but I can't find a reference that says TES-295 meets the TES-389 spec. I don't know if there's something about the PS system that would care about any difference.

--- Found ref from the engineer that wrote the spec - 295 can be used where DEX III is specified:

Talking about 295:







I suspect Tiffin and Bay Diesel don't use TES-389 fluids and the power steering systems seem happy enough :-).

This sparked a brain cell from reading a powerglide chassis owners guide and in it referenced - "Factory filled with Allison approved TES-295 fluid. To maintain these service intervals, fluid must not be mixed with
Dexron or other fluids." in the transmission section...

Keep probing ekim...

[Lt Dan]

Originally Posted by shepardmike

This sparked a brain cell from reading a powerglide chassis owners guide and in it referenced - "Factory filled with Allison approved TES-295 fluid. To maintain these service intervals, fluid must not be mixed with Dexron or other fluids." in the transmission section...

Keep probing ekim...

The transmission in the Power Glide chassis is filled with TES-295 long life fluid from the factory. I confirmed that with the chassis shop a couple of years ago when I changed out the transmission filters. I don't know about the power steering since it says Dexron III only, but I've used Dexron III/Merc compatible fluid and hopefully that's okay.

[ChiefBob]

This what I use in my 2024 Phaeton on a Powerglide chassis.

[Handyman99]

Originally Posted by bldski

I have tried to search this forum with no success.

So here goes, I have tried to find the correct power steering fluid for by Tiffin 45OPP but no success.
It would be great if someone on this forum could provide me with the correct fluid.

I’m pretty sure your 450PP is a Freightliner custom chassis (FCCC). You can download the service manual from the freight liner FCCC website.

On page 46/1 of my manual it calls out the following power steering fluid: Automatic Transmission Fluid Dexron® III

Most modern Dexrin III compatible fluids will be better. It’s also printed in the reservoir.