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So I serviced my LML Allison today.... used the new Allison preferred fluid, the Castrol 668 fluid.

Is this stuff for real? 4 years or 300,000 miles between services in normal situations?

Dang.... that's a long way!!!

I've always used TES-295 prior, did a single drain and refill at 50k miles, and a double dump and refill + new internal filter every 100k miles. Spin on filters every 30k miles..... NEVER had a single transmission issue.

I think with this 668 stuff I'll go 150k miles then double dump it and refill + new internal filter and skip the 50k service all together....

Thoughts from those who actually use it , appreciated..... Thanks

Bob

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Hey Bob good to see you back. I still use the 295 fluid.
 

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Gotta use up the 295 I have first. Everything I've read about the 668 is pretty impressive. Also glad to see you back Bob! 👍
 
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