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Taking Allison fluid sample

I am going to change the filters in our Allison this week. Can I just catch some of the fluid during the filter change? Will that be an adequate sample?
Allison Service Tip #1796, Rev. B speaks to installing an Push Button sampling valve (see attached) installed in an oil galley with constantly circulating fluid. It also states the fluid s/b 140 degrees F or the engine at operating temperature. Anyone know what size the Main-Pressure Tap plug is (I don't think I can change the filters with fluid that hot.
I have a report done from 2011 (also attached). I cannot tell from the report what lab did the analysis. I ordered an analysis kit from Pacific Detroit - Allison in Coberg, OR for a little north of $50.00 along with two gallons of Transynd at $39.00 each.
Any advice appreciated.
Thanks, Dick
Dick, '03 U320 40' Tag, 2 slides, Coach #6075
Full Timers
2009 Honda CR-V

Re: Taking Allison fluid sample

Reply #1
I use a sampling hand pump from Blackstone with plastic tubing down the dipstick tube.
Regards,
Brett

'99 42' Foretravel Xtreme
'14 Brown Motorsports Stacker
'05 Chevy SSR
'02 BMW R1150R

Re: Taking Allison fluid sample

Reply #2
I use a sampling hand pump from Blackstone with plastic tubing down the dipstick tube.

That's what we just did, pump from JG Lubricant services who also did our analysis.
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: Taking Allison fluid sample

Reply #3
Dick, I also use the hand vacuum pump from Blackstone Labs. putting the tube down the dipstick pipe. The oil should be hot for a proper reading of your sample.
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: Taking Allison fluid sample

Reply #4
If you are changing the fluid, clean the bottom of the transmission very well-- that keeps dirt from getting into the filter caps or drain plug.

Remove the drain plug.  Let at least one gallon flow out, then capture a sample.  You are good to go.

Sure, if not changing fluid, you could use a pump.

Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

 

Re: Taking Allison fluid sample

Reply #5
Got the fluid sample; kind of messy. Service guy at Allison shop told me to clean thoroughly around the Main-Pressure Tap plug, then when fluid is hot, loosen plug and catch sample. Replacing that plug with a valve would sure make it easier. Purge 3 or 4 ounces then take sample, leave plug in place (it has a protective screw-on cap).
Sample is in the mail.
The analysis kit from Allison cost $52.13. I just talked to Blackstone and they will do analysis for $35. Allison seems quite interested in the Total Acid Number (TAN). Blackstone will do that also, but have to request it. Also have to send a sample of unused fluid. Allison limit is +3 above unused fluid. TAN is included in above cost.
Dick
Dick, '03 U320 40' Tag, 2 slides, Coach #6075
Full Timers
2009 Honda CR-V