sierrastarr1@sbcglobal.net Report post Posted August 4, 2017 Last Fall after having a new transmission seal and new brake shoes put on the pilot shaft (1999 Beaver Patriot, Cat 3126B) I converted to synthetic transmission fluid after checking with the folks at Allison headquarters. Fast forward a few months and my parking brake is soaked in fluid and nearly useless again. I checked in with installing truck/motorhome repair shop that did the work and the foreman checked in with Allison and they told him not only is there NOT a seal that will hold up to the synthetic but I will develop other leaks as well!! What the Hay???? As mentioned I spoke with Allison BEFORE making the change and got the OK from them. I must say the transmission runs much cooler with the synthetic, which is great, but what a mess now!Repair shop foreman has a buddy that has worked at local Allison certified repair shop and is waiting to hear back believing there nay be an aftermarket seal that will work. Anyone out there have any information and or HELP for this situation? I can't be the only one that's run into this. Thanks Phil 1999 Beaver Patriot Ticonderoga in Beautiful shape. Share this post Link to post Share on other sites
wolfe10 Report post Posted August 4, 2017 Phil, Welcome to the FMCA Forum. You are right, never heard that one. And have used Transynd in all our Allison transmissions, including 1993 and 1997. I would be looking for an Allison authorized shop, not a truck/motorhome repair shop. Share this post Link to post Share on other sites
erniee Report post Posted August 4, 2017 I had Inland Truck in Dallas work on my prior coach- 97 Wanderlodge, after squirrels ate the wiring. They replaced the fluid with synthetic and never had any leaks. I'm with Brett- go to an Allison specific shop Share this post Link to post Share on other sites
garyreed Report post Posted August 4, 2017 Phil, You might be getting a snow job. It is true that in some cases synthetic oils will leak when used with old seals but with new seals there should not be an issue. That seal may have been damaged during instalation, It does take a special installer. Gary Share this post Link to post Share on other sites
wildebill308 Report post Posted August 4, 2017 Well just maybe they used an aftermarket part instead of a Allison part and installed it poorly and damaged it. Now it is CYA as they don't want to be on the hook for re doing the job. I would go to a certified Allison shop. By the way Welcome to the forum. Bill Share this post Link to post Share on other sites
five Report post Posted August 5, 2017 Any "synthetic" transmission fluid won't work. It must be the one Allison uses (or from their approved list)....Transynd. Share this post Link to post Share on other sites
sierrastarr1@sbcglobal.net Report post Posted August 5, 2017 First thank you all for your responses so far, I appreciate them all. I did use a synthetic that is on Allison's approved list. Transyd is not the only synthetic transmission oil on their list....there are several. So I rule that out as the cause. I will be talking to Allison come Monday morning and am interested in hearing from others with thoughts, experiences, expertise etc.. Thank you all again Phil Share this post Link to post Share on other sites
desertdeals69 Report post Posted August 5, 2017 I have used synthetic oil in two different MD3060s, 98 vintage in the last 18 years. The spec for the fluid is TES 295 if I remember correctly. Share this post Link to post Share on other sites
garyreed Report post Posted August 5, 2017 Bill, I think you hit the nail on the head they may be trying to pass the buck. There are a lot of independent shops that can do the right work but they are hard to find. Gary Share this post Link to post Share on other sites
rsbilledwards Report post Posted August 5, 2017 I had Stewart and Stevenson in Denver do a change over 2 years ago, not sure how good a job they did but not a leak any where. I intend to change the fluid in my Panther in September myself and do not expect any leaks. I have changed all other fluids to synthetic and no leaks. I run synthetics in a couple Audis and some VW corrados and a Golf no leaks after the change. Sounds like an excuse to avoid a mistake Share this post Link to post Share on other sites
wildebill308 Report post Posted August 5, 2017 10 hours ago, RSBILLEDWARDS said: I had Stewart and Stevenson in Denver do a change over 2 years ago, not sure how good a job they did but not a leak any where. I intend to change the fluid in my Panther in September myself and do not expect any leaks. I have changed all other fluids to synthetic and no leaks. I run synthetics in a couple Audis and some VW corrados and a Golf no leaks after the change. Sounds like an excuse to avoid a mistake When you do the change, be extremely careful when cleaning any stuck on old gasket. I recommend using a plastic scraper on the aluminum. If you use a steel scraper you can scratch the surface and create a leak path. This is mainly on the filter housings as it is a thin paper gasket. The one other potential problem is to use a good torque wrench. The torque is pretty high for bolts going into a aluminum casting. Going over the called for torque will make more work. All in all it is a simple job just like changing the oil. Just 2 internal filters to change. Bill Share this post Link to post Share on other sites
rlbarkleyii Report post Posted October 1, 2017 Many oil suppliers sell oil that they say is TES 295 spec lubricant. Don't take a change on the TS-295 spec or compliant oils, as they are generally NOT approved by Allison or else they would be on Allisons list. Allison often does oil analysis on all fluid in trannys coming in for service, especially warranty work. If it is not a approved supplier on their list they will not stand behind warranty. OUCH! Share this post Link to post Share on other sites