Community Forums

4x4van · 07-08-2017, 01:00 PM

Finally got around to draining the Dexron from my Allison 1000, replacing the spin on filter, and refilling with Transynd. To be honest, I only assume that it is Dexron; 2004, new to me, 27,000 miles, no idea of previous service...so I figured I might as well do it. Easy job, took about 2 1/4 gallons. Will do it again next year (likely after about 2-3000 miles) to accomplish the full change-over. The old fluid actually looked really good; nice bright red (just a bit darker than the new Transynd), no burnt smell, no debris on the magnet. Most difficult part was refilling; the position of the dipstick/fill tube behind the hood made it necessary to use a small container and refill it multiple times. Not enough room to tip the gallon jug up to the funnel. Wow, what a long dipstick! About 6 1/2 feet!

One final idea: Why can't all transmissions have a drain plug like the Allison?

DD788Snipe · 07-08-2017, 02:04 PM

For extra protection you can silicone a small magnet to the bottom of the filter to catch any metal before it enters the filter. Just a little added protection.

4x4van · 07-08-2017, 04:33 PM

There is already a large magnet in the base of the filter. Thanks to this forum, I knew about it and knew to swap it to the new filter. Otherwise it would have likely just gone in the trash with the old filter.

davebw31 · 08-17-2017, 08:33 PM

Next time you change the fluid let the coach set for 5-6 weeks without running the engine as this procedure allows all of the fluid in the clutch packs, valve body, fluid passages, and the most important is that the fluid in the torque converter drains in to the pan. I have read that there are 5-6 quarts always in the converter. I found this information on a few web sites about switching from Dexron to Trans-Synd.

Because you did not do this your fluid is diluted by the old fluid and therefore you will not get the full benefits of the Trans-Synd fluid, such as better fluid shear when hot and extending the maintenance interval.

If you had done this when you changed the fluid you would not have to do it again for 50,000 miles? Of course you will still need to change the external spin on filter every 5,000 miles.

My coach had 16,000 miles when I switched to Trans-Synd except I added some items to improve reliability. I bought a cast aluminum pan with internal/external fins (helps removed heat from fluid) that added 3 quarts more capacity (total now 17 1/2 qts), an Allison deep pan filter with an extension tube, added a dash trans temp gauge with the sensor mounted in the bottom of the pan (second best place to get accurate temp.) and of course the spin on filter.

i did all this to improve reliability, lower maintenance costs and longer fluid change intervals, and the fact that I tow a 24' Pace American enclosed low profile race car trailer. It weight loaded is 9,500 #s (GVWR is 11,400 #s), I currently have 41,500 miles on my coach and I would estimate that 90% of those miles was towing the trailer.

The only time I exceeded my normal 100* (flat roads) to190* (7% grades) temp was when I got lost and got on a road that went up a pretty steep high mountain (was over 7% grade) in Tenn. and temp max. out at top of climb at 260*...........! ouch. I stopped at a pull-off and idled for about 1/2 hour. In the first five minutes temp went down to 210* and in the next 25 mins. it was at 100*.......!

Glad I did my "homework" and did the mods. and fluid switch that I did, because it probably saved me $3,000-4,000 in a trans. rebuild.

If I was not towing a large trailer and only towing a toad I would have still made the changes. I think I spent between $450.00 and $500 for everything in parts and my labor was FREE. The most expensive parts was the deep finned trans. pan @ $150.00 (+ shipping) and the 5 gals. of Trans-Synd @ $140.00 ($28.00 a gal.) were the most costly.

Winemaker2 · 08-18-2017, 05:50 AM

davebw31...
Where did you find Transynd for $28/gal? I'm used to almost $50/gal?
Also surprised at the new alum pan for $150 but I've never looked at that...

70ChevelleSS · 08-18-2017, 06:11 AM

The spin on filter does NOT need to be changed every 5,000 miles. It needs to be changed initially at 5,000 miles then every 50,000 for general, not severe, duty. When the 2nd change is done you can use the Allison change intervals for 100% TES 295 fluid. Fluid change at 150,000 miles for general use. Internal filter is only changed during a trans overhaul.

hzjcm8 · 08-18-2017, 08:46 AM

Quote:

Originally Posted by DD788Snipe

For extra protection you can silicone a small magnet to the bottom of the filter to catch any metal before it enters the filter. Just a little added protection.

DO NOT introduce RTV (silicone) into the pan as this may result in excessive foaming of the transmission fluid.

4x4van · 08-18-2017, 09:36 AM

Quote:

Originally Posted by davebw31

Next time you change the fluid let the coach set for 5-6 weeks without running the engine as this procedure allows all of the fluid in the clutch packs, valve body, fluid passages, and the most important is that the fluid in the torque converter drains in to the pan. I have read that there are 5-6 quarts always in the converter. I found this information on a few web sites about switching from Dexron to Trans-Synd.

Because you did not do this your fluid is diluted by the old fluid and therefore you will not get the full benefits of the Trans-Synd fluid, such as better fluid shear when hot and extending the maintenance interval.

Not an Allison transmission expert, but I do know that there is no "low point" drain on a torque converter; at least none that I've ever seen. Letting it sit for any amount of time, while getting a bit more from the clutch packs, valve body, and passages, won't drain the fluid from the converter. Everything I've read, including from the Allison expert here on iRV2, says it takes 2 drain/fill procedures to change over from Dexron to Transynd. If you didn't do it twice, then your fluid is still diluted with Dexron.

DD788Snipe · 08-19-2017, 12:19 AM

Quote:

Originally Posted by hzjcm8

DO NOT introduce RTV (silicone) into the pan as this may result in excessive foaming of the transmission fluid.

Clarification: silicone the small magnet to the outside of the filter.

davebw31 · 09-17-2017, 05:37 PM

I change my spin on more often because of the weight of the race car trailer, high southern/south western temps. and I do a lot of mountain driving.

Funny after draining mine after coach sat for 5 weeks I measured fluid drained and it came to just slightly less than 15 quarts!

dbarton291 · 09-17-2017, 06:22 PM

Quote:

Originally Posted by davebw31

I change my spin on more often because of the weight of the race car trailer, high southern/south western temps. and I do a lot of mountain driving.

Funny after draining mine after coach sat for 5 weeks I measured fluid drained and it came to just slightly less than 15 quarts!

Some of what you may be seeing is from the cooler and cooler lines slowly draining back. The longer it sits, the more oil does drain from the clutches and gear pack, etc into the pan.
Take a look at a cross section of the transmission sometime. The torque converter drains back from the same place it's fed. That's through the ground sleeve/turbine shaft area. The torque converter is always half full no matter how long the vehicle sits.