Fluid Change Intervals

[circle5]

Well i seen this Forum had no posts so i figured i'd bust the cherry

How often do you 7.3 guys change your fluids?
I change my oil every 3500. Trans Fluid 30-40K.
And my Fuel Every 5-700 Miles :D
What other one's do you guys change regularly?

[bboone52]

I am glad you busted the cherry. I was going to change the trans fluid on my New to me 2002 F350 and was advised aginst it. Was told unless the transmission fluid had been changed regularly every 25 to 40K miles it could cause the transmissin to fail. Apparently the plates shed particals and the particals are suspended in the fluid which keeps the whole thing togeather. New fluid , no particals and the tranny slips. I have 175K on the truck and do not know when or if it has ever been changed. Sooooo wadda U tink about dat???

[Carssuck]

uhhh, I don't quite know what to say about that..:eek:

Stop changing the oil too, as the oil ages it gets thicker and any leaks you may have will go away too! LOL!:D

[PSDPlayer]

Well either you change it and it fails because the fluid doesn't hold it together or you don't change it and the bearings and bushings give out since the viscosity and thermal protection of the oil is gone.

[_CH_]

two words:
saw dust

:D

[PSDPlayer]

Saw dust flows great through shift solenoids.

Oil normally goes about 5k miles on the regular stuff. The 7.3s we used to have got Valvoline All Fleet Plus 15w-40 this was before the premium blue existed.

Trans fluid in the 4r100 and e4od should run the Mercon stuff and it can go about 30k miles, however if you tow heavy stuff all the time then keep an eye on it. Mercon V has some friction modifier additives in it that in the older transmissions like E4OD will cause some pretty bad slipping.

Fuel filters should be changed between 10-15k miles deppending on how much you you use. If you do alot of idling then you may need to change them sooner. If you get some fuel from a low quality source or you store fuel then you may need to change them sooner.

One of the biggest things in the 7.3L is the COOLANT if you neglect it you will be buying a block. The coolant should be changed every 2 years at the most. But its so cheap to change annually why wouldn't you do it. DO NOT FORGET THE COOLANT ADDITIVE. The is a scaling additive that is added to the coolant that bonds to the walls of the cylinders. When the explosion in the cylinder happens you get a little cavitation on the walls where small air bubbles in the coolant exist. The additive flakes off of the walls instead of the metal erroding.

Diff Fluids are usually factory fill with synthetic and should run up to 100k miles. But if you tow or live in a hot climate you should change it sooner. The 10.5 and 10.25 axles use 75W-140. The Dana 80 uses 75w-90. The S110 in a 450/550 uses 75w-140. Front axles run 80w-90. And don't forget the friction modifier for the trak-lok axles. This stuff also lubes the axle bearings so when you fill it up you need to let it fill the axles tubes as well and then check the level.

[_CH_]

Saw dust flows great through shift solenoids.


yup

[lukecline]

amsoil syn engine oil every 3k
reg ol tranny fluid 20k
coolant- well this build 20k LOL

I run Cat ELC pre deluted coolant in my truck, supposed to be ok to run 100k miles iirc. Tranny fluid i just run the cheap stuff since the trans builder thought syn oil was a waste for high po builds. Trans works awesome so i'll be going back with the el cheapo tranny fluid.

[heinzboy]

oil every 3 thousand miles? Damn that = alot of cash for oil changes.

[lukecline]

Uhh yeah i beat on my truck pretty hard. Figure the least i can do is keep fresh oil in it. It'll be getting rotella for 1500 miles (3-4 oil changes) before i switch it back to amsoil (fresh build).

[Coltaine]

Changing too often can be bad too I hear, I never really understood it but.. What the hey.

[Lord Tauk]

Welcome to 3 years ago

[SINNER]

I change engines every 30k, fluid changes are for pussies.