Former Allison Oils Engineer Back and Ready for Questions

[Dave1956]

Tom welcome back and thanks for all of your information! I have three Allison 3000 questions after reading through my manual:
(2003 Newmar DP with Freightliner, Cummins, Allison 3000)
1. Is it safe to shift directly from R to D or the reverse as long as the engine is at normal idle? Or must I first go to N?

2. From reading the manual I get the sense that when I digitally shift the tranny down to a lower gear, say when I am in up and down hills, that it automatically stays in a "lower range". Does this mean that it now does all of its shifting and stays at or below my new gear selection?

3. I have read that it is OK to place the tranny in say 5th gear in order to drive at a slower speed, increasing engine RPMs and avoid "gear searching". Is this true and safe to do for extended periods of time with the cruise control?

Thanks for your time,

Dave

[Pigman1]

Quote:

Originally Posted by hzjcm8 Pigman 1, I reviewed your report and it looks good. The lab defaults to a more conservative sampling interval in case you're sampling the transmission along with the engine since the engine should be sampled more frequently. I'm typically OK with folks sampling their transmissions annually (independent of miles). I wouldn't worry about the zinc unless it gets above 200 ppm at the next sample. It's way too low to be from engine oil (if that was ever added by mistake). I suppose it could be coming from a zinc-chromate coating from a bolt or fastener in the transmission. The particle counts are good and the ISO Cleanliness Code (23/19/15) is really good. In fact it's better than the clean oil spec we had at Allison which was 24/20/15. Keep in mind that the filters on your 3000MH transmission are around 50 micron; so anything smaller will typically pass through the filters. If you were to extrapolate the data between 38 and 70 microns, you've only got around 10 particles per milliliter at 50 microns which is very good. This indicates you have very little debris in the system and that the filters are still working great. Based on what I see, I'd say you're good to 75,000 miles without a problem. At that point, I recommend you change the filters and top it off with TranSynd. Then, run it an additional 75,000 miles with fluid sampling an annual basis or perhaps every 25,000 miles (if you want more data). PS: If you want to try extending your filter change intervals, then don't change anything at 75,000 miles and begin sampling every 10,000 miles using the Ultimate Kit with particle count. This will keep you safe while extending both the fluid and the filter change intervals as much as possible for maximum savings. Let me know which way you want to go and I'll help you review the data along the way.

WOW! Super good info. I'll pull the filters at 75,000 and top it up with TranSynd. Since we're running around 20,000-25,000 a year, an annual test sounds about right. I do ALL my own work, so I know nothing has been near the trans fill port but the TranSynd I replaced when I did the original filter change. We also have been testing engine oil and to make it easier, I'll be switching over to JG for that process too. With the Cummins on a 20,000 mile interval it makes the scheduling much easier.

Thanks again for making a very complex subject a whole lot easier for us RV'ing grease monkeys.

[hzjcm8]

Quote:

Originally Posted by Pigman1 WOW! Super good info. I'll pull the filters at 75,000 and top it up with TranSynd. Since we're running around 20,000-25,000 a year, an annual test sounds about right. I do ALL my own work, so I know nothing has been near the trans fill port but the TranSynd I replaced when I did the original filter change. We also have been testing engine oil and to make it easier, I'll be switching over to JG for that process too. With the Cummins on a 20,000 mile interval it makes the scheduling much easier. Thanks again for making a very complex subject a whole lot easier for us RV'ing grease monkeys.

Pigman1,

You're quite welcome. I like working with you guys !!!

[hzjcm8]

Quote:

Originally Posted by Dave1956 Tom welcome back and thanks for all of your information! I have three Allison 3000 questions after reading through my manual: (2003 Newmar DP with Freightliner, Cummins, Allison 3000) 1. Is it safe to shift directly from R to D or the reverse as long as the engine is at normal idle? Or must I first go to N? 2. From reading the manual I get the sense that when I digitally shift the tranny down to a lower gear, say when I am in up and down hills, that it automatically stays in a "lower range". Does this mean that it now does all of its shifting and stays at or below my new gear selection? 3. I have read that it is OK to place the tranny in say 5th gear in order to drive at a slower speed, increasing engine RPMs and avoid "gear searching". Is this true and safe to do for extended periods of time with the cruise control? Thanks for your time, Dave

Dave 1956,

Answers:

1. Is it safe to shift directly from R to D or the reverse as long as the engine is at normal idle? Or must I first go to N? Yes. It's safe to shift from R to D at idle. The transmission controls logic will allow this and it will drop and apply clutches as necessary and with the correct timing.

2. From reading the manual I get the sense that when I digitally shift the tranny down to a lower gear, say when I am in up and down hills, that it automatically stays in a "lower range". Does this mean that it now does all of its shifting and stays at or below my new gear selection? Yes. That is correct. If you go to a specific gear, it will not shift above that gear but will do all the programmed shifting at the programmed shift points below that gear.

3. I have read that it is OK to place the tranny in say 5th gear in order to drive at a slower speed, increasing engine RPMs and avoid "gear searching". Is this true and safe to do for extended periods of time with the cruise control? Yes. This is why it's called an "automatic transmission". All of the gear changes, clutch apply patterns, and shift points are programmed into the TCM and it can run there all day long. It will restrict the engine speed so as not to overdrive the transmission. The controls are programmed to limit the input torque, HP and speed so as not to over stress the internal parts.

Hope this helps !!!

[hzjcm8]

Quote:

Originally Posted by genesimmons can you tell me if a 07 bounder/workhorse with 6-speed allison came with transynd as factory fill?i cannot find anywhere that says it came with dextron or transynd.thanks

Sorry,

Don't know the answer to that one. I'd call the RV manufacturer and give them the VIN.

[edgray]

Workhorse began filling all the Allison trannys used in their RV chassis with TranSynd beginning with chassis produced on and after June 6, 2005. Ed

[Dave1956]

Thank you sir!

[hzjcm8]

All,

So we don't have too many threads going on Allison fluids and fluid changes, let's all go back to the original thread which can be found at http://www.irv2.com/forums/f125/former-allison-transmission-fluids-engineer-89293-10.html.

All questions for me should be listed there so I don't miss any.

Thanks !!!!