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Ford differential lube?

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what is my HP?

Which Exhaust?

The Fords, at least back around the same time as my '02 Dodge was built, used the same Dana differentials as my truck does - and since there is a local Ford dealer and no dodge dealer for 70 miles, might use the differential lube Ford sell for their trucks.



Anyone have any reason to offer as to why I shouldn't do that? I've been using straight Valvoline semi-synthetic with decent results, but suspect the stock lube is slightly more aggressive as to limited slip operation. And since we're in snow country now, and will be RVing in more remote and unimproved areas, want as positive a LS function as possible with my rearend.
 
any GL5 rated gear lube will be fine... synthetic is my preferance... doesn't need to be something that is a dealer overpriced item
 
Hey Gary, how are ya ? My oldest son works for Dupratt Ford here in Dixon and for the 02 F-250's & up, they use the same weight oils as our Dodge axles except Ford is Manditory synthetic and factory filled with synthetic, at least that is what my son said. Also since you left civilization why don't you just order on line like rpmoils/Royal Purple, or Amsoil ? and make the UPS driver find you. Take care, Mike.
 
Gary, you might buy a bottle of Ford's friction modifier though if you use their oil and add it in alittle at a time if your diff. starts to chatter around turns. Put some in and do some figure 8's until the chatter goes away. If you let the dealer do it they won't waste the time and will just dump the whole bottle in or 2 bottles lowering the friction of the limited slip clutches. Mike
 
Well, I bought 4 quart bottles of the Ford stuff (only took a bit over 3 quarts to fill) - nearly had to mortgage the house, the stuff was $17 a quart.



Yup, it was full synthetic, and 75/140 wt. I also got a bottle of their friction modifier as well, and we'll see if THIS full synthetic allows my LSD to work better than the Amsoil I tried a while back...



Anyway, the new stuff is installed, and we'll see how my LSD clutches react over the next few miles...
 
Gary - K7GLD said:
and we'll see if THIS full synthetic allows my LSD to work better than the Amsoil I tried a while back... ...



Hate to tell you, Gary, but it won't. Almost EVERy full synthetic gear oil that's shelf-stocked has a lot of modifier in it. Combine this with the fact that it's synthetic, which is slipperier. NOW, add in the fact that it's a heavier lube, and you will have very poor LSD function.



For the price you paid, you could have easily bought some Mobil 1, or Valvoline Synthetic. Heck, you could have splurged and bought Redline or Royal Purple for $8/qt.



Then again, who knows what role local availability plays in your calcluation of value.



Redline DOES offer a full synthetic gear oil that does NOT come with modifier in it. Just look at their 75w-90NS or 75w-140NS gear oils. The NS stands for NO SLIP.



I'm going to try them on my next change. Then I can add the level of modifier I want to have instead of settling for a too-loose diff.



Justin
 
Gary,



I tried Royal Purple for a while and ended up taking it out due to chatter. Tried the modifier and it worked for a month or so. Then switched to Amsoil, had to add modifier to it as well to stop the chatter. Added a second bottle after about 6 months and then about a month later it started again. The lube was thin when I drained it.



I have gone back to Valvoline gear lube (NOT synthetic) and added modifier to that. Used the new Amsoil modifier. (Funny they came out with that since they say no modifier is needed with the Amsoil lube!) Have made a trip to Washington and back pulling a flatbed and so far everything is nice and smooth. I think I'm just going to stay with the conventional oil and change it every 10K or so(or until it starts to chatter). I have the Mag Hi-tec cover so draining it is easy.



NOTE: I'm not flaming any product, just stating how they worked in my truck. Some trucks seem to be fine with the above synthetics but some seem to not like them. Mine is old and cantankerious, seems to like the conventional better.

Stan
 
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Gary,

I run 75w140 in my rear diff.

Ford synthetic, I got a good deal off of Ebay on a bakers dozen.



All be it, this is in a 3rd gen.
 
Ford Oil is good, but other synthetics do a better job. Ford Friction Modifier is good stuff. I know Rearend Specialties in Santa Clara, Cali, swears by GM Friction modifier. I took my stang in for at least (4) different gear swaps, and they put the Ford "FM" on the shelf, and add GM "FM". I was running an Auburn locker... . Oo. But I changed the rear end oil out, and used Ford "FM"... :D
 
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Too early to tell how the Ford stuff is working - not enough miles yet - but our RV trip up to a nearby lake this weekend should put the test to the lube, as well as the new 1. 6 injectors and 4 inch exhaust - unfortunately, it's a pretty curvy/steep road, so can't get the speed up for a REAL test like the California Sierra over Hwy 50 and 80...



Yeah Hohn, if I'd known going in the Fomoco lube was so high priced, I'd have made other plans, but what the hell, I was already there and had the stuff in hand, and no other local alternatives...
 
paccool said:
I have gone back to Valvoline gear lube (NOT synthetic) and added modifier to that. Used the new Amsoil modifier. (Funny they came out with that since they say no modifier is needed with the Amsoil lube!)
The reason Amsoil came out with the Friction Modifier in a sperate package is as you say. Some people do not want to use a synthetic or the Amsoil Gear lube, but do want a Friction Modifier, hence a seperate package of the Friction Modifier.



Wayne

amsoilman
 
My only real concern over possible differences between the Dana 80's used in the Fords vs our trucks, is the variation in how the internal LS clutches can be arranged to fit different applications - it's entirely possible Ford uses ALL the clutch discs in an active position, where Dodge only uses part of them - that COULD seriously slew how the Ford differential lube would function in a Ford application as compared with my Dodge.



Time will tell...
 
Why in the heck did you drop the Valvoline Semi-synthetic oil. I started using it several years ago (on your advice) and wouldn't think of trying anything else.

Towing max GVW from Idaho to Mexico and back every year and I've had zero problems. Also... I like products that can be purchased at Auto Zone or NAPA.

Mike
 
mhenon said:
Why in the heck did you drop the Valvoline Semi-synthetic oil. I started using it several years ago (on your advice) and wouldn't think of trying anything else.

Towing max GVW from Idaho to Mexico and back every year and I've had zero problems. Also... I like products that can be purchased at Auto Zone or NAPA.

Mike



Mike, the Valvoline DID work quite well for me, and unless I start seeing some additional LS action from the Ford stuff, I very well might return to the Valvoline semi-synthetic before next winter. And it IS the greater need for aggressive LSD action that prompted me to make the change back to an OEM lube - the Valvoline was very good - but not QUITE as aggressive as the stock DC stuff was. That was great, even beneficial, in the dry California circumstances I most often drove in - but up here in eastern Oregon, without 4WD, I need all the reliable traction I can get in ice, snow and mud.



I'm pretty convinced that aggressive LSD action comes at a price, and that price is added LS clutch wear and other differential stresses - the OEM differential lube I first drained from my truck way back after buying the new truck, clearly had a lot of particles floating around in it - though the LS action WAS very nice and positive. The Valvoline still provided very adequate LS action, and was nearly as clean and pure when I drained it a week or so ago, as it was outta the bottle. :D



Decent traction combined with low wear and stress is USUALLY a GOOD thing! :-laf



I only changed the stuff because of time and miles, plus wanting slightly more traction, and there aren't any Kragens or similar stores out here in eastern Oregon - though the local NAPA store could probably get me some of the Valvoline if I specifically asked for it - which I might do, if the Ford stuff doesn't work out! :rolleyes:
 
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