Syn rear end Oil ???

[speedracer67]

i have Ram 3500 4WD C & C Flat bed. Use for oil field hauling with a goose neck trailer.
Do I need to change to Syn oil for the rear end?
Haul about 15,000 lb loads, mostly Highway to rig locations.
In Texas 90% of the time.
TIA

 

[dexter]

Yes, and front also - recommended every 20K when you tow a lot.

Don't forget the transfer case - 60K

 

[SyN]

Synthetic gear oil would not be a bad choice.
The only Con to synthetic is price.

 

[69GWC]

Red line and Amsoil are 2 great choices for gear oil.

 

[dexter]

Synthetic gear oil would not be a bad choice.
The only Con to synthetic is price.

I got Lucas 75w90 from Summit for 9.99 - he'll need 6.

Free shipping for over $100 which the OP can do with oil change, oil filter, air filter.


Also, get this and more vinyl hose that fits into the hose provided. You shove the small hose into the gears and suck out the old fluid. Then just pump in the fresh!

https://www.amazon.com/Lumax-LX-118...rd_wg=LqQ1r&psc=1&refRID=RJHJM28DST562N8NKHWT

 

[speedracer67]

I have had te truck serviced at Dodge 4 or 5 time now (108,000 miles) and they have not changed the gear oil or mentioned the syn to be used. do I need a additive for the limited slip diff?
Thanks for the advice.

 

[SYKRAMMAN]

Should really pop the cover off to clean the magnet. Jmho.

 

[Rampant]

I have had te truck serviced at Dodge 4 or 5 time now (108,000 miles) and they have not changed the gear oil or mentioned the syn to be used. do I need a additive for the limited slip diff?
Thanks for the advice.

Synthetic yes. Additive, no. HDs do not have clutches in the diffs, so no additive is needed.

From the owner's manual:

"Front and Rear Axle – 2500/3500 Models:

We recommend you use SAE 75W-85 HD Ram GL-5 Synthetic Axle Lubricant. Limited slip additive is not required for Limited-Slip Rear Axles."

Also, your truck definitely falls into the "Severe Service" category. Diff fluid should be changed every 20k miles:

"2500/3500 Models:
Inspect the front and rear axle surfaces. If gear
oil leakage is suspected, check the fluid level. If using your vehicle for police, taxi, fleet, off-road
or frequent trailer towing, change axle fluid."

(Can't copy and paste the maint sched chart, but the first "X" is in the 20k mi or 2 yrs column for diff fluid)

 

[R.L.K.]

Imo with what your doing with your truck you should be changing your Differential oil about every 3rd engine oil change interval or 20k whichever comes first .

Synthetic oil would be preferred , either Redline or Amsoil SG oil would be my top two choices in that order .

Sent from my SM-G930V using Tapatalk

 

[speedracer67]

Thanks to all for the advice.

 

[loveracing1988]

Should really pop the cover off to clean the magnet. Jmho.

The magnet is in the fill plug.
Synthetic comes in the axles from the factory. Also like said above 2500's don't have clutches yet so no additive is needed.

Sent from my LG-H918 using Tapatalk

 

[Nick@GotExhaust]

These guys got you covered on info and i can help you with fluid. let me know if you would like a quote. Also if interested it may not be a bad idea to get a aftermarket diff cover that gives you more capacity. It will help keep the diff cooler.

 

[SYKRAMMAN]

The magnet is in the fill plug.
Synthetic comes in the axles from the factory. Also like said above 2500's don't have clutches yet so no additive is needed.

Sent from my LG-H918 using Tapatalk

O, ok, thought it was in the same location as the 9.25 rear. Learn something new everyday.

 

[speedracer67]

Get an after market for rear only or front and rear?

 

[Nick@GotExhaust]

Get an after market for rear only or front and rear?

you should be fine with just rear unless you are towing in 4wd

 

[htwo]

I run Amsoil gear oil in all my diffs. I don't have a 3500 but would definitely change it every 50K miles as it's still cost effective for the slightly added cost over conventional gear oil when you change that sooner. You can effectively run longer intervals with having an open differential. Amsoil says up to 250K but as mentioned it's good to remove the cover and inspect at least every few years.