Allison Transmission Questions

[AllisonMan]

Hi there. I have worked on Allison Transmissions for 27 years. If you have any questions, please post and I will check back once a week and try to answer them all. Thanks and have a great day!<font size="2"></font id="size2">

[herbneffie]

Hey AllisonMan, I own a 2000 Safari w/CAT 330
and Allison 3060 World trans. The fluid/filter was changed at 5k by dealer. Is the next f/f change due at 25k or 30k? I want to do the change myself. Can I use after market filters or should I
use Allison filters? Don't want to mess up my
warranty. I prefer to stick with Dextron III.
The trans temp runs at normal and below and the
fluid is clear, clean and has no burnt odor after
16k miles. The trans shifts smoothly, however I
get some violent downshifts when using the pac brake unless I engage the pac at below 35mph.
Downshifts are sometimes harsh at other times without using the pac, usually in stop and go
situations. Any advice on servicing and operation
of the 3060 trans will be appreciated.

[AllisonMan]

Hello herbneffie,
Your next fluid change would be at two years or 23,000 miles whichever comes first since with Dexron III they lowered the interval to 18,000 miles from 25,000.I recommend Allison filters just from experience. I have seen some aftermarkets collapse and totally burn up the transmission. Have you considered synthetic Transynd? It costs double a normal Dexron service, but you have no time limits and can go 50,000 miles and just have the filters changed and an oil sample done. The fluid will not need to be changed until the oil sample comes back saying it needs changing. This usually means only one oil change for the life of your motorhome as long as you do the samples and filter only changes at every 50,000. It really is cost effective in the long run. I have seen a truck with 190,000 miles and original transynd, come back with ok readings (but the customer changed anyway, he figured he got his moneys worth)
As far as the harsh engaugement of downshifts while your exhaust brake is on, does it preselect 2nd or 4th? If it preselects 2nd when you let off the throttle, you should take it to your nearest Allison Distributor and have it set to 4th preselect. (I do it for free but I cannot say about other distributors) This takes about 5-10 minutes if you know where your DDL (computer plug) is. If it already preselects 4th, we can opt to change to 5th but not recomended at all because 5th is overdrive and you will pick up speed if you do not watch your speedometer.
Downshifts during exhaust brake function always seem a little harsher due to a higher calibrated shift. Stop and go harshness around town, try hitting the mode button. That should solve that problem.
I hope this answers your questions.

[herbneffie]

AllisonMan, thanks much for your advice. I will
contact the Allison Dealer in Ocala FL for some price
quotes on the service and 4th preselect change.
Glad you are aboard the forum for expert advice.
Regards, herbneffie

[AllisonMan]

Hello again herbnellie,
First off, thank you. I was also curious about service intervals because Allison changes them all the time. I went to work today and get my service letter from Allison. Here are exact Allison service intervals.
Dexron III: 25,000 miles or 12 months.(I told you different last night sorry so your service should be at 30,000 miles)Filters are the same intervals.
Transynde synthetic:Fluid 150,000 miles or 48 months and the filters 75,000 or 36 months.We suggest having an oil sample every 2 years with synthetic.
I hope this does not confuse you but it is hard to keep track with all the different models and oils nowdays.
Again thank you for your kind words and I enjoy solving questions, it is a challenge sometimes but I know all the Allison engineers in Indy and if I don't know the answer, I will find out! Have a great day.

[herbneffie]

AllisonMan, thanks for the re-post information.
Looks like Transynde is the best way to go.
Thanks again, herbneffie

[AllisonMan]

herbnellie,
If you ever travel to the NW (Portland area Allison Dist), please stop in and say hello. Allisonman

[herbneffie]

AllisonMan, thanks for your invite to Oregon, same
offer from here, just fire me an e-mail to let me
know you are coming. Hope you didn't mind me sending
IU Fan to you, we are both members on another forum.
Thanks for your help.
herbneffie

[Butch]

Allison Man, I have to jump in here now with a question. How is reprogramming from 2nd preselect to 4th preselect going to enable the transmission to downshift with less "harsh engagement"??? Once this reprogramming has been accomplished, the operator will have to manually select lower gears for down shifting thereby negating a very useful function of the exhaust brake...is this not correct??? My particular unit is set for 2nd as preselect and while it does down shift to 5th then on to the next lower gear as speed / RPM permits, it is sometimes harsh depending on what was done at the service. BUT, the transmission seems to eventually get back to my style of driving and stay in that mode until the next time.....(I would personally prefer this shift pattern with 2nd preselect as it gives me one less thing to contend with)

[AllisonMan]

Hello Butch,
I agree that your coach may be set-up for you correctly, but you are in the minority. I get around 5 reprograms to 4th a month and I have yet to get a negative response. When my customers come in for a service, I like to take them on a test drive with me to explain the functions of the shift tower and pre-select differences. I do have some that like the 2nd preselect and that is totally ok. The customers satisfaction is what is important to me. The problem lies that if you do have rough shifts, you cannot choose a higher gear than 2nd, but if you have a 4th preselect, you do have the option to select a lower gear but 4th does a very good job of braking your coach. As long as you are happy Butch, that is all that matters. IU Fan and herbnellie were not pleased with the performance with 2nd preselect, I am only giving them an option to try. I am sure they will be very happy. Different coaches have different differential gears which usually is the reason for one customer being happy with 2nd and another with 4th. I hope this answers your question Butch. As I do to every question or comment, I invite you to stop in any time if you are in the Portlad, OR Allison distributer area. Have a great day.