BAC Forum

General Boards => Technical Support => Topic started by: Bill Lampkin on April 30, 2021, 04:50:35 PM

Title: Tranny fluid and filters
Post by: Bill Lampkin on April 30, 2021, 04:50:35 PM: Is it time I had the tranny fluid and filters changed? Coach has 55k miles, no issues with tranny. Allison 4000. Fluid level ok checked via shift keypad.
Title: Re: Tranny fluid and filters
Post by: Bill Lampkin on April 30, 2021, 04:57:42 PM: Question #2- I just looked at the Allison website, and it says to use Transynd TES 668 starting Jan 2021. Anyone have info on replacing with TES 668 vs TES 295 (Transynd)?
I was thinking it might be time for new fluid and filters just based on the age of the coach not on mileage. Any ideas?
Title: Re: Tranny fluid and filters
Post by: Bill Lampkin on April 30, 2021, 05:01:27 PM: Found this on the difference between 668 and 295

https://www.truckinginfo.com/10126901/new-transmission-fluid-spec-for-allison-improves-performance-protection#:~:text=TES%20668%20builds%20on%20the,modifier%20durability%2C%20according%20to%20Allison.&text=DuraDrive%20HD%20Synthetic%20668%20will%20have%20the%20same,recommendation%20as%20TES%20295%20fluids.
Title: Re: Tranny fluid and filters
Post by: Bill Lampkin on April 30, 2021, 05:07:21 PM: And then there is this from Allison:

https://www.allisontransmission.com/docs/default-source/aftermarket-brochures/sa8742en-tes668-brochure_f_rev.pdf?sfvrsn=2189e81d_0
Title: Re: Tranny fluid and filters
Post by: Steve Huber on April 30, 2021, 09:00:15 PM: Bill,
IMHO 295 has been working in Allison trannys for many years and I'm not aware of any significant problems with the units. So, not sure why one would want to change and probably pay more $ for the new fluid.
Steve
Title: Re: Tranny fluid and filters
Post by: Keith Phillips on April 30, 2021, 10:07:40 PM: Bill fluid analysis will tell you the condition of your fluid, it may be good for many more miles.
Title: Re: Tranny fluid and filters
Post by: Bill Lampkin on April 30, 2021, 10:48:45 PM: Fluid analysis, that's what Allison says. But they say compare your sample with an original sample (from an new trans, I guess). They say change fluid if the difference between the old and new sample differs by xx%, which is good advice if you have that original sample. They also say 300,000 miles or 4 years, whichever comes first. Just wondering what others do. We only put on about 3,000 miles per year on the Beaver. I had the tranny fluid replaced this year in my Jeep Liberty, shifts like new now.
Title: Re: Tranny fluid and filters
Post by: Keith Moffett Co-Admin on May 01, 2021, 03:04:47 AM: Bill, our 07 came with Transend. Our 98 did not and so when service time came we did filters and upgraded to Transend only to have shifting issues. Dextron was thin enough but much thicker Transend did not seem to flow as well through passages and cooler tubes that had 12 years of plaque.
Just my 2 cents.
Title: Re: Tranny fluid and filters
Post by: Bill Sprague on May 02, 2021, 03:54:53 PM: I am a fan of Blackstone Labs for oil analysis. Attached is an actual report from when I had a Beaver and was getting analysis done by them.