OEM coolant and diff fluid change

[Mikie12]

It's time to change my original engine coolant and diff oil. I went to my local dealer to obtain the proper MOPAR fluids, however the MOPAR coolant and the diff oil has a part# different from what my service manual/owner's book specifies.

For instance, the book calls for 9 1/4 AA - MoparT Synthetic Gear Lubricant 75W-90, w/o limited slip additive, but what the dealer had was 75W-85 Mopar Synthetic Gear Lubricant (part#68210057AB)

Question: Is this the proper diff replacement oil, is it a bit too thin for frequent towing, and does it or does it NOT need the additive? The counter man did offer a Mopar Synthetic Gear Lubricant 75W-140, in light of the towing should I opt for the heaver oil? And if so, does that go for both front and rear diffs, or maybe run the heavier oil in the rear diff and put the 75W-85 in the front?

Also, when changing the diff oil, should I clean the reusable gasket and place a film of oil on the rubber like you do with the oil filter gasket?

On the coolant, the dealer sold me the Mopar 5yr/100K coolant (part#68048953AB), but my book calls for the same coolant but a different part# (part#5011764AB).

Question: Is this the right coolant which just an updated part#? Also, does anyone know if there is a block drain plug so I can get most of the old coolant out w/o having to refill the radiator with distilled water and run the engine to temperature 50 thousand times to get all of the old coolant out?

I think that's all for now, thanks in advance for your time and knowledge, Michael

 

[GrantP]

You might be overthinking this..I think I'd return all that stuff to the dealer if the price is not comparable to aftermarket stuff. Any synthetic 75W-90 is fine for the axles, there is no need for LS additive since there are no clutches in the diff. You could also run 75W-140 (I do) if you like. As far as the coolant, get some Xerex G-05 and you're good. My .02.

 

[DaveHess]

X2 with Grant. I run Red Line 75W-90 in the front differential and 75W-140 in the rear. I also use Zerex G-05 for Coolant. As for the reusable gasket, When I still had the stock cover, I put it on dry and no problems. I also used a torque wrench to tighten the cover.

 

[Prairie Dog]

X3. Mopar is stupid expensive on their rebranded elixirs.

 

[sag2]

You have a $12k engine and a $3k differential so put whatever you want in it. No sense going with what it's supposed to have when you can save $30 every 5 years or so.

 

[Killer223]

OMG!!!! if you are intent on staying with the mopar items, don't worry about it, part number's change. as for the 75/85 vs the 75/140, If you tow heave day in and day out get the 140, else the 75/85 will be just fine.
the front only needs the 75/85,
that said mopar gets their oil from the big oil producers, so you could safe money by going to your local auto parts house, napa, checker, autozone, etc, and safe a good chunk of change using valvoline, penzoil, supertech, brands of oil and not fear any issues.

as for the coolant you can get and OAT coolant and be fine.

 

[diesel_driver]

"For instance, the book calls for 9 1/4 AA - MoparT Synthetic Gear Lubricant 75W-90, w/o limited slip additive, but what the dealer had was 75W-85 Mopar Synthetic Gear Lubricant (part#68210057AB)"



I just went through this with my 2004. I went to a smaller dealer about 40 miles from home (great prices compared to my local dealer) for Mopar 75W-90 for my front and rear diffs, and they sold me the 75W-85, saying this was the new (and cheaper) OEM recommended fluid. When I got home, I contacted Fiat Chrysler support to get the official recommendation. They replied right back, and stated that the proper fluid was in fact the 75W-90. The 75W-85 is specific for one model, not any of the Ram trucks, but one of the smaller car/SUV's. I don't recall which model, but it was listed in the "recommended fluid" chart I received.

The dealer said they were under the impression that 75W-85 was a superseded oil to the 75W-90, but turns out they were wrong.

 

[DaveHess]

BTW Killer223, you and I exchanged some thoughts on the CI-4 oils in another post. Decided on the Red Line 15W-40 and a once a year oil change. I just did the math the other night and only put 4,800 on the clock last year. I know it's not what you would do but at the end of the day, I sleep better. Keep the thoughts coming! Oh! I use the 75-140 in my rear differential for two reason. One because 75% of the time there is a trailer hanging on out back and two, I was noticing a slight "howl" from the rear diff on deceleration. The 75-140 took care of that.

 

[Mikie12]

Thank you all for your responses, I wanted to keep it OEM if I can, but sounds like I’ll need to switch to aftermarket lubes like some you mentioned, in fact since they removed some of the detergents from the motor oil to preserve the DPF (exhaust diaper) I’ve been running RedLine 15W-40 100% syn since then. I think the problem is the parts sales people aren’t very well informed witch is why I turned to you for your opinion. I’ll return the 75W-85 to the dealer and exchange it for their 75W-140 for the rear diff, is it OK to run the lighter 75W-85 in the front diff only? I think the coolant they sold me is the HOAT (pink stuff) my book specifies despite the different part#, but I’ll confirm it when I go to exchange the diff oil.Is there a drain plug in the block to fully drain the coolant?

 

[Killer223]

BTW Killer223, you and I exchanged some thoughts on the CI-4 oils in another post. Decided on the Red Line 15W-40 and a once a year oil change. I just did the math the other night and only put 4,800 on the clock last year. I know it's not what you would do but at the end of the day, I sleep better. Keep the thoughts coming! Oh! I use the 75-140 in my rear differential for two reason. One because 75% of the time there is a trailer hanging on out back and two, I was noticing a slight "howl" from the rear diff on deceleration. The 75-140 took care of that.

the redline is a fine product. i know once a year is what most do, but with that quality of oil you could easily double that. it would have no problem going 10K, or 2 years.
yes it's your truck, do as you see fit. OMG $50 a gallon? ouch!!!!
the 140 in the dif is fine, it's even better if you tow, there are a lot of these trucks that NEVER see a trailer behind them. and no reason for the heavier oil. it just hurts MPG's till it's warm.

as far as the coolant, HOAT will be fine, although i thought these were switched to OAT around 07-08, i could be wrong though, i use the Shell ROTELLA®ELC from walmart with no issues, one truck is 245K the other is 160K i changed mine around the 80K mark.

 

[Mikie12]

That's a good idea, i'll contact Chrysler on Monday, give them the VIN#, and ask what it's supposed to have with the appropiate part numbers. How did you contact them, did you just call the 800#?

 

[Mikie12]

Yup, $150. plus the FleetGuard filter. And something else on that (don't tell anybody I know-they'll give me a butt kickin for sure) but I got busy the last 5 years, moving to another state, and remodling the house we bought and forgot about the motor oil. I looked last week and noted that I'd last changed the oil (with RedLine) summer of '09, and pretty close to 15K miles on the oil now. Will grab a sample from the drain stream and submit it to Terry Dyson for analysis to see how bad it is. Hopefully RedLine did it's job offering some lasting protection.

 

[GrantP]

Please post the results when you get them.

 

[Mikie12]

Good idea, I'll do that...

 

[JR]

After 8 years I'd expect the TBN to be all but gone...Once the acids from the fuel starts to mix with the detergents the oils biological clock starts ticking....Which is why there's a change recommendation based on time regardless of miles/hours. Once the TBN is depleted the pH of the oil will begin to attack the engines internals. It is no secret oil can go much further than the recommendations set forth by OEM's but it is impossible to know how much further (or longer) without analysis. It will be a very interesting report to see how the oil has held up over the long haul.
Please do post up your results!

 

[cerberusiam]

I was noticing a slight "howl" from the rear diff on deceleration. The 75-140 took care of that.

Be advised the howl was there because something is wrong, it will resolve itself probably at the wrong time. The OE bearings had more than few issues and once they started howling the gears were out of alignment for some reasons.

Valvoline 75-90 is the factory fill in the diffs, no reason to run 75-140 unless you are maxxed or over weight and in high heat conditions all the time. The hit is in the wallet when you run the heavier fluids. You can put the gasket on dry after cleaning. Just make sure the sealing surface is clean and smooth, and, ding the cover holes back out with a ball peen hammer.

Premium Blue 15-W-40 is the choice per Cummins, no real reason to run anything else with those miles per year. Just change it out at the start of the warm weather to get rind of the accumulated moisture.

Zerex G5 is the usually fill on the coolant. You can use the Mopar stuff but nor real benefits as the others is available almost anywhere. Stick with HOAT in case you get in a bind and have to mix. There is no way to completely drain the block unless you stand it on end, and, all the contaminants will be in the bottom part that stays. hence the reason to flush until the drain is clean.

 

[sag2]

The diff fluid should be 068218655AA ($22.70 list price) and is full synthetic 75w-90. The 75w-140 (68218657AA $29.70 list price) is listed for the Dana 60 axles. The coolant is HOAT and is PN 68048953AB ($23.95 list price). All can be found online for less.

 

[Mikie12]

Good info, thanks cerb

 

[Mikie12]

The diff fluid should be 068218655AA ($22.70 list price) and is full synthetic 75w-90. The 75w-140 (68218657AA $29.70 list price) is listed for the Dana 60 axles. The coolant is HOAT and is PN 68048953AB ($23.95 list price). All can be found online for less.

Thanks SAG, that's what I was looking for, I'll take those # to the deal tomarrow and get the correct diff lube. The coolant they sold me appears to be correct as it matches the p/n you provided above.

 

[DaveHess]

Yikes Cerb!!! Like I don't have enough to worry about! I first noticed it about 12 years ago. It was only on deceleration and going down hill. And barely discernible. Haven't heard it since. My newest worry is the two power steering lines going to cooler are both leaking. From where I cannot locate. The drips are located about a half inch back from where they connect to the cooler. Basically where the lines level out. I rag wrench the lines and a couple days later the drip is back. The short rubber hose is dry above the drip. The line that goes to the "T" is hard to tell since it has the sheath around it but the "T" is grimy. The steering gear box is above these two lines and is dry. This is why I don't sleep well.....