Just bought a new to me 04 F350 with only 30,000 miles from its original owner. The truck is almost like showroom condition. Normally, I would be changing all the fluids, but the owner's manual states that under normal driving conditions, the rear diff is maintenance free and is filled for life. Your thoughts? Amsoil Severe Gear is my normal choice when I change diff oils.
Thoughts on Ford "lifetime" diff fluid
- Thread starter atc250r
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My thought is that nothing lasts for a lifetime. Especially fluids in vehicles.
Personally, I would change it. Maybe not at 30k, but by 60k, it would be changed.
I look at it this way. If you leave it in there for a "lifetime," you are taking the risk that it will hold up and that nothing is wrong. If you change it, you aren't taking that risk.
Personally, I would change it. Maybe not at 30k, but by 60k, it would be changed.
I look at it this way. If you leave it in there for a "lifetime," you are taking the risk that it will hold up and that nothing is wrong. If you change it, you aren't taking that risk.
I'd also change the fluid.
Is it a limited slip version? If so all that clutch material collects in the fluid and the only way to remove it is to drain it. I'd do it at the 30k service.
Otherwise, you could probably go longer. "Filled for life," I don't know about that. Check the fluid level occasionally.
Is it a limited slip version? If so all that clutch material collects in the fluid and the only way to remove it is to drain it. I'd do it at the 30k service.
Otherwise, you could probably go longer. "Filled for life," I don't know about that. Check the fluid level occasionally.
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Originally Posted By: atc250r
Just bought a new to me 04 F350 with only 30,000 miles from its original owner. The truck is almost like showroom condition. Normally, I would be changing all the fluids, but the owner's manual states that under normal driving conditions, the rear diff is maintenance free and is filled for life. Your thoughts? Amsoil Severe Gear is my normal choice when I change diff oils.
I have a 2010 FX4 and I changed mine at 13,300 and will again soon (when the oil hits 50K). I used MC 75W-140 on the first OC, but I have some Amsoil to replace it with this time. I suppose it depends on whether or not you tow quite a bit (or if the previous owner did). I would probably change it.
Here is my UOA oil the oil at 13,300:
MC 75W-140 @ 13,000 Miles
Just bought a new to me 04 F350 with only 30,000 miles from its original owner. The truck is almost like showroom condition. Normally, I would be changing all the fluids, but the owner's manual states that under normal driving conditions, the rear diff is maintenance free and is filled for life. Your thoughts? Amsoil Severe Gear is my normal choice when I change diff oils.
I have a 2010 FX4 and I changed mine at 13,300 and will again soon (when the oil hits 50K). I used MC 75W-140 on the first OC, but I have some Amsoil to replace it with this time. I suppose it depends on whether or not you tow quite a bit (or if the previous owner did). I would probably change it.
Here is my UOA oil the oil at 13,300:
MC 75W-140 @ 13,000 Miles
Originally Posted By: atc250r
Just bought a new to me 04 F350 with only 30,000 miles from its original owner. The truck is almost like showroom condition. Normally, I would be changing all the fluids, but the owner's manual states that under normal driving conditions, the rear diff is maintenance free and is filled for life. Your thoughts? Amsoil Severe Gear is my normal choice when I change diff oils.
A mechanic once told me that "lifetime" means "until it breaks because it needed new fluid." I'd change it.
John
Just bought a new to me 04 F350 with only 30,000 miles from its original owner. The truck is almost like showroom condition. Normally, I would be changing all the fluids, but the owner's manual states that under normal driving conditions, the rear diff is maintenance free and is filled for life. Your thoughts? Amsoil Severe Gear is my normal choice when I change diff oils.
A mechanic once told me that "lifetime" means "until it breaks because it needed new fluid." I'd change it.
John
Most of an axles lifetime of contaminants is generated within the first 5,000 miles, not to mention what was left in there from manufacture. Early changes followed by long intervals are the way to go. I vote change it now, install a good oil and go 60K or more as the operational situation dictates ( frequent hard use, towing, hauling, e.g. high oil temps, dictates short intervals, light use, everyday driving dictates, low oil temps, equals long use).
Another vote to change it as nothing lasts a lifetime.
I assert the same: change it now, your transmission will last much much longer than if you didn't. No such thing as a lifetime fluid.
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Originally Posted By: John_K
...A mechanic once told me that "lifetime" means "until it breaks because it needed new fluid." I'd change it.
John
This.
When I had my Malibu, the transmission was supposedly a "lifetime" fill and when I had about 60,000 on the car and it was in for service, the advisor suggested a fluid change. I said "I thought it was lifetime fluid" and he said "well, it is, but if you change it, your tranny will have a longer lifetime.".
Cheap insurance, IMHO.
...A mechanic once told me that "lifetime" means "until it breaks because it needed new fluid." I'd change it.
John
This.
When I had my Malibu, the transmission was supposedly a "lifetime" fill and when I had about 60,000 on the car and it was in for service, the advisor suggested a fluid change. I said "I thought it was lifetime fluid" and he said "well, it is, but if you change it, your tranny will have a longer lifetime.".
Cheap insurance, IMHO.
Originally Posted By: opus1
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When I had my Malibu, the transmission was supposedly a "lifetime" fill and when I had about 60,000 on the car and it was in for service, the advisor suggested a fluid change. I said "I thought it was lifetime fluid" and he said "well, it is, but if you change it, your tranny will have a longer lifetime.".
Quote of the day! Wonderful quip!
[
When I had my Malibu, the transmission was supposedly a "lifetime" fill and when I had about 60,000 on the car and it was in for service, the advisor suggested a fluid change. I said "I thought it was lifetime fluid" and he said "well, it is, but if you change it, your tranny will have a longer lifetime.".
Quote of the day! Wonderful quip!
You have an opportunity to get all of the break-in contaminants out of the differentials and transfer case. Change it now. Severe Gear is an excellent choice.
I dropped the factory-fill gear lube out of my F350 when it had 80,000 miles. There was a considerable amount of metallic "paste" on the magnets. I even did a UOA on the rear-diff fluid, as I recall it had over 1300 PPM or iron in it.
I dropped the factory-fill gear lube out of my F350 when it had 80,000 miles. There was a considerable amount of metallic "paste" on the magnets. I even did a UOA on the rear-diff fluid, as I recall it had over 1300 PPM or iron in it.
I would go ahead and change it. I dumped the factory fill on each of my Rangers at around 50K and it was nasty with a good bit of break in mess.
If you pull the fill plug, I bet there's a blob of metal pieces stuck to the magnet. That's not all of it.
The second fill can last longer if you use synthetic since the break in will be over with. I think Amsoil suggests 50K for severe service and 100K for normal driving.
If you pull the fill plug, I bet there's a blob of metal pieces stuck to the magnet. That's not all of it.
The second fill can last longer if you use synthetic since the break in will be over with. I think Amsoil suggests 50K for severe service and 100K for normal driving.
Kestas
Staff member
The word is that automakers are going to synthetic in differentials to boost CAFE numbers. Ideally, and for best economics, the initial break-in charge shoud be regular lube, changed out to synthetic after 3-5K.
I agree with all of them ^^^.
Repeat after me: "There's NO SUCH THING as lifetime fluid."
You may substitute "There's NO SUCH THING as filled-for-life" or any such statement.
Originally Posted By: opus1
I said "I thought it was lifetime fluid" and he said "well, it is, but if you change it, your tranny will have a longer lifetime."
Truest automotive statement evar.
Repeat after me: "There's NO SUCH THING as lifetime fluid."
You may substitute "There's NO SUCH THING as filled-for-life" or any such statement.
Originally Posted By: opus1
I said "I thought it was lifetime fluid" and he said "well, it is, but if you change it, your tranny will have a longer lifetime."
Truest automotive statement evar.
I think that every fill is a lifetime fill if you don't change it out. It will be in their for the life of the unit.
I favor the longer lifetime change.
I favor the longer lifetime change.
Originally Posted By: RF Overlord
Repeat after me: "There's NO SUCH THING as lifetime fluid."
You may substitute "There's NO SUCH THING as filled-for-life" or any such statement.
To paraphrase another poster, it depends on the lifespan. You can treat oil, transmission fluid, and differential fluid as lifetime fluids, but only if you want the components to have a short lifespan.
Repeat after me: "There's NO SUCH THING as lifetime fluid."
You may substitute "There's NO SUCH THING as filled-for-life" or any such statement.
To paraphrase another poster, it depends on the lifespan. You can treat oil, transmission fluid, and differential fluid as lifetime fluids, but only if you want the components to have a short lifespan.
I change my rear diff oils at 50k or when I first acquire a used vehicle. Cheap insurance.
Many drivers(at least in So Cal) think that these are lifetime fluids: Antifreeze, Brake, Power Steering, ATF, Diff and MTF.
Saw many supposed performance cars such as BMW, Audi, MB ... at my trusted shop have above OEM fluids, even the cars have more than 100k miles and more than 10 years old. The only fluid they change regularly is oil(and oil filter). The other items they don't like to replace is engine air filter and cabin filter.
Saw many supposed performance cars such as BMW, Audi, MB ... at my trusted shop have above OEM fluids, even the cars have more than 100k miles and more than 10 years old. The only fluid they change regularly is oil(and oil filter). The other items they don't like to replace is engine air filter and cabin filter.
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