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Topic: Transmission Synthetic Fluid Conversion (Read 1299 times) previous topic - next topic

Transmission Synthetic Fluid Conversion

Just completed the second fluid change and now 100% synthetic. I found that the local Allision dealer had the best price on High Capacity filters ($53),  eliminating all the research for a suitable replacement. Their kit P/N is 29548988. In addition to all the gaskets it also includes a replacement "o" ring for the drain plug.
The selected media item is not currently available.Bob & Faith Rozek
1997 U320 40'
Xtreme Remodel
2010 Scion XD

Re: Transmission Synthetic Fluid Conversion

Reply #1 –
Bob,

Did you notice any difference in trans or retarder after you filled her up with that liquid gold? 

Chuck
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS

Re: Transmission Synthetic Fluid Conversion

Reply #2 –
Hi Chuck
I have the Silver Leaf program that I use to monitor and document data.  I did observe a drop in overall transmission temp. and a substantial drop in temp between the petroleum and synthetic fluids when using the retarder.  Heat is the enemy.
The selected media item is not currently available.Bob & Faith Rozek
1997 U320 40'
Xtreme Remodel
2010 Scion XD

Re: Transmission Synthetic Fluid Conversion

Reply #3 –
I run the same mountains all the time and also have Silverleaf. Noticed over a 20 degree rop in temp and it took longer to heat up too.  Now I did not graph it but the hill slowed the coach to 45 mph climbing up and there was a reduced limit on the down side of 35 mph.  I have many other hills I drive too living by the skyline drive as I do.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: Transmission Synthetic Fluid Conversion

Reply #4 –
I don't have Silverleaf, but I do know that synthetic will handle heat much better than dino will.  My MT643 four speed transmission had already been changed over to Allison  TranSynd®, before I brought it.  I did another change, because time wise it was long overdue.  The engines oil pan has Shell Rotella T6 full synthetic in it.  That oil has been well documented as a outstanding oil for the Cummins 5.9 B6 engine.  And the rear differential will have Pennzoil full synthetic 75W-140 GL5 gear lube oil in it next week. 

I have been using full synthetic oil products since Mobil 1 was introduced in the mid 1970s.  All my vehicles run synthetic oils.  My 2002 VW Jetta diesel requires synthetic motor oil.  It gets its oil changed at 18,000 mile intervals.  Has 200.000 miles on the odometer.  Sets outside and starts right up in sub O weather.  The DWs car and the tractor get the garage in the winter time.  And the tractor does not like to start unless it is plugged in.  And I need the tractor to keep the driveway cleared out!  So the little 3 cyl Kubota diesel gets pampered!
1994 U225
build #4514

Re: Transmission Synthetic Fluid Conversion

Reply #5 –
Hey Pat,
I started converting our coach over to Amsoil synthetic lubes about two years ago. The M11 and power steering system have SAE 15W-40 Heavy-Duty Diesel and Marine Motor Oil. The M11 has a bypass filter system. Oil has been in service for two years and tested semi annually. The rear differential and front wheel bearings have  80W-140 GL5 gear lube.
After all the conversions were complete, with the exception of the second transmission fluid change, I was able to document close to a 1 mile per gallon increase by utilizing the Silverleaf program.
The selected media item is not currently available.Bob & Faith Rozek
1997 U320 40'
Xtreme Remodel
2010 Scion XD

Re: Transmission Synthetic Fluid Conversion

Reply #6 –
Interesting on the mpg.  I know I have a bit over 97K on this coach and the MPG have increased  since I hit 80K.... I will it 8.2 on the flat lands and 7.2 in the mountains.  When I bought the coach it had about 60K on it and a 6.8 mpg overall average and now I am about 7.7 mpg.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: Transmission Synthetic Fluid Conversion

Reply #7 –

Quote
I started converting our coach over to Amsoil synthetic lubes about two years ago. The M11 and power steering system have SAE 15W-40 Heavy-Duty Diesel and Marine Motor Oil

Bob,
Have you noticed any change in the fan seals or steering box seals sense you have changed over? (seals seeping) We have been looking for someone that has went this way as we are due to have the oil and filters changed on the Hyd. system and were looking at Amsoil.

Pamela & Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Transmission Synthetic Fluid Conversion

Reply #8 –
Hi Pamela and Mike
I make it a practice to keep mechanical components clean so I would see any leaks that might occur.  I have not found any leaks associated with the synthetic fluid conversions. I am a Amsoil dealer and have been using their product since 1982.  Amsoil synthetic products have an excellent track record in regards to conversion leakage.  They are true synthetic products and do not contain petroleum additives.  I did find a leak, unrelated to the synthetic oil conversion, on the engine fill tube.  It had a number of hairline cracks where the gussets are welded to the tube at the elbow.  I elected to remove the tube completely and blank off the opening.  This tube is not properly supported and even if it's repaired, I believe it can be a constant source of problems.
The selected media item is not currently available.Bob & Faith Rozek
1997 U320 40'
Xtreme Remodel
2010 Scion XD

Re: Transmission Synthetic Fluid Conversion

Reply #9 –
Quote from: flite2010 –
I did find a leak, unrelated to the synthetic oil conversion, on the engine fill tube.  It had a number of hairline cracks where the gussets are welded to the tube at the elbow.  I elected to remove the tube completely and blank off the opening.  This tube is not properly supported and even if it's repaired, I believe it can be a constant source of problems.

Is this the dipstick tube that caused Steve and Ginny some problems in this thread?

Dip stick tube

Is this perhaps an inspection item to be added to the "50 things before you buy" list? 

Michelle
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: Transmission Synthetic Fluid Conversion

Reply #10 –
No, this is the engine oil fill tube, not the dip stick.
The selected media item is not currently available.Bob & Faith Rozek
1997 U320 40'
Xtreme Remodel
2010 Scion XD

Re: Transmission Synthetic Fluid Conversion

Reply #11 –
I had the transmission rebuilt due to severe vibration in coach. P3 bearing was bad.
Inland in Dallas did rebuild in 2009 and I was told transmission was good for 150k before any service is needed with TranSynd.

Larry Bradley
1998 U270
2011 Jeep Grand Cherokee
Larry Bradley
SOB
former 1998 U270
Build 5251
Jeep Grand Cherokee

Re: Transmission Synthetic Fluid Conversion

Reply #12 –
Hi Larry
Do you have a retarder?  If so, Allison recommends a change at 75,000 miles.    Bob
The selected media item is not currently available.Bob & Faith Rozek
1997 U320 40'
Xtreme Remodel
2010 Scion XD

Re: Transmission Synthetic Fluid Conversion

Reply #13 –
Thanks Bob.

I do have a retarder.

Larry Bradley
1998 U270
Grand Cherokee
Larry Bradley
SOB
former 1998 U270
Build 5251
Jeep Grand Cherokee

Re: Transmission Synthetic Fluid Conversion

Reply #14 –
I just called to get a quote for Transynd conversion from an Allison dealer here in Jacksonville, Fl. It was $389 . He also told me it will take three fluid changes to be completely synthetic. I was surprised. I thought it would be much more expensive. I guess I will get it done this week.

Mark
The selected media item is not currently available.
Mark and Tanya
Milton , Florida
US Navy Veteran (DV)
1999 U270 Special 40' CAI , 2015 Jeep Wrangler Sahara
 

Re: Transmission Synthetic Fluid Conversion

Reply #15 –
Mark,

Check the Allison recommendations.  You only need two changes to shift to the synthetic schedule.
Regards,
Brett

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