On Monday I decided to pull the trigger and go synthetic in the F/R Diffs, TC and Power steering..
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Cool.... results?
If you end up doing the engine, make sure you get a can of flush or you will changing your oil sooner. This is because the synthetics do a better job of keeping things clean.
This weekend was a bust, had to do some PM on theLexus.
In prep for the engine going synthetic, I went with Castrol Synthec and will transition to Amsoil after 2-3K miles inclliding their oil filter
I am doing rear diff this week and based on many threads may go conventional in the front diff.
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Whats the concern here with the front diff, that the gear lube gets into the Birfs?
Not sure it has to do with gear oil migrating past the oil seal. I run synthetic in the pumpkins and don't have problems. It has more to do with how much you wheel and under what conditions. If I was doing a lot of wheeling with water crossings or mud I would be more apt to do frequent changes. Using synthetic makes it much more costly in this scenario and unneeded. I would still use synthetic every where else.
Buck
Whats the concern here with the front diff, that the gear lube gets into the Birfs?
Yes and No. Yes gear lube does get into the knuckles, but really the reasoning is that the knuckle grease slowly gets past the seals and into the diff lube contaminating and thickening the oil. This is the reason for dark black or green gear lube (depending on the knuckle grease) when drained.
Tools R Us recommends more frequent drain/fills for the front diff with a cheaper conventional diff lube. I agree. And by frequent he means every other engine oil change...
Synthetic will test your seals and if they are tired you'll find out.
Synthetic will test your seals and if they are tired you'll find out.