Oil change & gear lube underfilled?

[RHOfan]

Prepping for my 1st oil change, so tried to find an RHO oil change video on YouTube. None. But, a few on TRX. Interesting, the Hellcat has an oil cooler that also has a drain plug. Wondering about the RHO…anyone know if the engine in RHO has a separate oil cooler with its own drain?

Also, watched a few gear lube videos & two mentioned the front diff takes 1.5qts, but 99% of TRXs have only 1qt installed at the factory. Has anyone checked this on their RHO? Same for the transfer case…1/2qt low is common, but that unit takes 2.5qts, so not as big a deal.

 

[out]

Prepping for my 1st oil change, so tried to find an RHO oil change video on YouTube. None. But, a few on TRX. Interesting, the Hellcat has an oil cooler that also has a drain plug. Wondering about the RHO…anyone know if the engine in RHO has a separate oil cooler with its own drain?

Also, watched a few gear lube videos & both mentioned the front diff takes 1.5qts, but 99% of TRXs have only 1qt installed at the factory. Has anyone checked this on their RHO? Same for the transfer case…1/2qt low is common, but that unit takes 2.5qts, so not as big a deal.

No Separate oil cooler and drain on the RHO. Good to see they put the filter under the truck instead of on top like the 3.6. Much easier and less mess underneath.

 

[RHOfan]

Just completed my 1st oil change on RHO at 1206 miles…why?

This engine is very similar in output & configuration to the current BMW M3/4 Competition. BMW recommends that engine & all differential fluids be changed at 1200 miles. They are so serious about it, BMW even pays for this $2400 service.

Our differentials are not limited slip, so I’m just going to follow the “severe duty” recommendation of checking/changing the fluid at 30K miles, though I will probably confirm the front diff is full at some point in the near future (many came 1/2 quart low in TRX).

Transfer case is another story. Since there are clutches & slip (heat), that one is getting fluid changed out at 2500 miles.

For the oil filter removal, I used a 74/76mm 15 flute cap. The drain bolt is 13mm. I drained approximately 7 3/8 quarts total from the engine & filter. Guessing the additional 1/8 quart is in the filter media. The MOPAR filter part# is 68566307AB, and I got .4 quarts into it before install. Oil is factory spec Penzoil for SRT 0W-40.

Easy peasy. No need to remove any skid plates or jack it up. Though, a 6” socket wrench extension is highly recommended (by me).

I don’t have any torque specs for the drain plug or filter…did them by feel, as I’ve done for many vehicles over the years. The oil filter does have a pictorial on the side that appears to indicate it should be hand tightened + one turn. Maybe my hands are too strong (ha!), but 1/4 turn with the wrench after hand tight felt PLENTY snug!

 

[Cautionary Tale]

Just completed my 1st oil change on RHO at 1206 miles…why?

This engine is very similar in output & configuration to the current BMW M3/4 Competition. BMW recommends that engine & all differential fluids be changed at 1200 miles. They are so serious about it, BMW even pays for this $2400 service.

Our differentials are not limited slip, so I’m just going to follow the “severe duty” recommendation of checking/changing the fluid at 30K miles, though I will probably confirm the front diff is full at some point in the near future (many came 1/2 quart low in TRX).

Transfer case is another story. Since there are clutches & slip (heat), that one is getting fluid changed out at 2500 miles.

For the oil filter removal, I used a 74/76mm 15 flute cap. The drain bolt is 13mm. I drained approximately 7 3/8 quarts total from the engine & filter. Guessing the additional 1/8 quart is in the filter media. The MOPAR filter part# is 68566307AB, and I got .4 quarts into it before install. Oil is factory spec Penzoil for SRT 0W-40.

Easy peasy. No need to remove any skid plates or jack it up. Though, a 6” socket wrench extension is highly recommended (by me).

I don’t have any torque specs for the drain plug or filter…did them by feel, as I’ve done for many vehicles over the years. The oil filter does have a pictorial on the side that appears to indicate it should be hand tightened + one turn. Maybe my hands are too strong (ha!), but 1/4 turn with the wrench after hand tight felt PLENTY snug!

GREAT INFO! Thanks for being awesome and sharing the knowledge wealth

 

[RHOfan]

When I drained, I got almost 7.5 quarts out. Refilling, I only put 7 quarts back, including filter pre-fill. I figured a little under-filled is better than overfilled. When I ran the process to update the oil level gage, it showed 1 bar below Max. Per the manual, this is “OK”.

Since 4 bars below max requires adding a quart of oil, 1 bar is likely 1/4 quart below max fill. I’m ok with that. Way better than overfilling.

 

[gram10]

Just completed my 1st oil change on RHO at 1206 miles…why?

This engine is very similar in output & configuration to the current BMW M3/4 Competition. BMW recommends that engine & all differential fluids be changed at 1200 miles. They are so serious about it, BMW even pays for this $2400 service.

Our differentials are not limited slip, so I’m just going to follow the “severe duty” recommendation of checking/changing the fluid at 30K miles, though I will probably confirm the front diff is full at some point in the near future (many came 1/2 quart low in TRX).

Transfer case is another story. Since there are clutches & slip (heat), that one is getting fluid changed out at 2500 miles.

For the oil filter removal, I used a 74/76mm 15 flute cap. The drain bolt is 13mm. I drained approximately 7 3/8 quarts total from the engine & filter. Guessing the additional 1/8 quart is in the filter media. The MOPAR filter part# is 68566307AB, and I got .4 quarts into it before install. Oil is factory spec Penzoil for SRT 0W-40.

Easy peasy. No need to remove any skid plates or jack it up. Though, a 6” socket wrench extension is highly recommended (by me).

I don’t have any torque specs for the drain plug or filter…did them by feel, as I’ve done for many vehicles over the years. The oil filter does have a pictorial on the side that appears to indicate it should be hand tightened + one turn. Maybe my hands are too strong (ha!), but 1/4 turn with the wrench after hand tight felt PLENTY snug!

did you do the transfer case or any diff fluid changes yet? If you, what fluid did you end up going with?

 

[RHOfan]

did you do the transfer case or any diff fluid changes yet? If you, what fluid did you end up going with?

Not yet, Gram10…just hit 2K miles.

But, I’ll be using the BW fluid for the transfer case.

Second guessing myself on 2500 mi interval. Saw one changed out at 5K, and fluid still looked fresh after some semi-abusive driving in a Hellcat equipped truck. I think my biggest concern was addressing a possible underfill situation with the fluid swap, but have seen a few RHO with good levels from the factory.

Still pondering…

 

[Cautionary Tale]

Not yet, Gram10…just hit 2K miles.

But, I’ll be using the BW fluid for the transfer case.

Second guessing myself on 2500 mi interval. Saw one changed out at 5K, and fluid still looked fresh after some semi-abusive driving in a Hellcat equipped truck. I think my biggest concern was addressing a possible underfill situation with the fluid swap, but have seen a few RHO with good levels from the factory.

Still pondering…

I'll be doing all fluids (minus oil) end of March and doing analysis plus physical inspection of fluids. I'll be around 2500 by then and will share results.

 

[gram10]

I'll be doing all fluids (minus oil) end of March and doing analysis plus physical inspection of fluids. I'll be around 2500 by then and will share results.

What fluids are you going to use?

 

[Cautionary Tale]

What fluids are you going to use?

BW on xfer case and whatever dealer reccomends for trans

 

[gram10]

BW on xfer case and whatever dealer reccomends for trans

Diffs?

 

[RHOfan]

BW on xfer case and whatever dealer reccomends for trans

By “trans”, you mean transmission? If yes, why are you changing the fluid so early? You’ll need a new trans pan, too. Yikes!

 

[Cautionary Tale]

By “trans”, you mean transmission? If yes, why are you changing the fluid so early? You’ll need a new trans pan, too. Yikes!

LOL, yeah, that's the plan but I might hold off til 10-15k on that. I do it way early because of all my past vehicles have benefited from getting the metal particles out, at least that's how I justify it Analysis only catches the particles smaller than we can see with human eye and there have always been plenty of those to justify an early first transmission fluid change. Never owned a RAM so this will be a new experience.

 

[Cautionary Tale]

Diffs?

I bought AMSoil for diffs, its in picture I posted in changing oil threads

 

[gram10]

I bought AMSoil for diffs, its in picture I posted in changing oil threads

oh yes, i saw you say you were going to use the same fluid in the front and rear, any reason for using the lighter weight fluid in the rear?

 

[405Forged]

I'll be doing all fluids (minus oil) end of March and doing analysis plus physical inspection of fluids. I'll be around 2500 by then and will share results.

Which place are you sending your samples too.

 

[RHOfan]

LOL, yeah, that's the plan but I might hold off til 10-15k on that. I do it way early because of all my past vehicles have benefited from getting the metal particles out, at least that's how I justify it Analysis only catches the particles smaller than we can see with human eye and there have always been plenty of those to justify an early first transmission fluid change. Never owned a RAM so this will be a new experience.

Just FYI…

The ZF unit has a filter & several strong magnets in the disposable pan. Ram says its lifetime fluid & fleet techs have reported few fluid relayed failures, even over 150K miles.

That being said, ZF recommends fluid changes between 60K-80K miles, depending on usage. It’s a sorta complex procedure that typically requires a lift & warming/shifting the transmission to prime the unit correctly.

 

[gram10]

Just FYI…

The ZF unit has a filter & several strong magnets in the disposable pan. Ram says its lifetime fluid & fleet techs have reported few fluid relayed failures, even over 150K miles.

That being said, ZF recommends fluid changes between 60K-80K miles, depending on usage. It’s a sorta complex procedure that typically requires a lift & warming/shifting the transmission to prime the unit correctly.

the process isn't too bad, I did it a few times in my BMW, which has an 8hp45, the hardest part was the lack of access to the fill plug(not relevant with this truck), outside of that it is easier than it appears.

 

[Cautionary Tale]

Just FYI…

The ZF unit has a filter & several strong magnets in the disposable pan. Ram says its lifetime fluid & fleet techs have reported few fluid relayed failures, even over 150K miles.

That being said, ZF recommends fluid changes between 60K-80K miles, depending on usage. It’s a sorta complex procedure that typically requires a lift & warming/shifting the transmission to prime the unit correctly.

Great info! Maybe I'll hold off on it, but I'll definitely get it done before 60k. I look at manual guidelines as bare minimum to keep a vehicle running until warranty runs out

 

[gram10]

fyi, stumbled upon this trx thread for gear oil changes. https://www.ram-trx.com/threads/dif...ase-fluid-change-my-observations.14346/page-5