Allison Transmission Questions

[BigHartz]

Allison Transmission Questions

Allison Man.. I have a 1999 30' 165K miles Blue Bird shuttle bus I will convert to a Class A motor home. It has a pusher 5.9 24V Cummins with 4 speed Allison auto-trans and I don't have the model #. Appears that the trans has been recently rebuilt and has Dexron III oil. This increase in weight plus pulling a 25' IO boat will require me to boost the HP output 50 to 80 HP. My questions are what can I do to add longevity to the trans. First I will add a trans temp gauge so what should I expect the normal operating temp to be? I see gauges full scale 250F and others 400F what should I use? Would you recomend a synthetic oil also? Thanks for what you do. Big Hartz

 

[mcbro]

Allison Transmission Questions

Allisonman,
I am new to this forum and a new RVer so please forgive my etiquette.

1> I have purchased a 1995 Monaco Crown Royal Signature series Pusher with a Cummins M11 with 81000K. The manual for the transmission is missing from all docs. All the previous owner said was that it was a bigger trans. because of the engine size. Do you have any idea which trans. the bigger one is or how I can tell by looking.

2> Being a new RVer I am learning as I go. I recently took a trip and had a little bit of an issue with over heating the coolant temp of the engine while climbing hills (pulling a Jeep Grand Cherokee on a car trailer). A friend told me to manually downshift while climbing. This seemed to help but I still believe that it is getting hot to fast. In just a few minutes of climbing the temperature will go from 185F to about 198F and then will stabalize as long as I keep the RPM above 2200 and may even drop a few degrees. Is it true that I should manually shift or is something wrong? The transmission temp runs from 175F to 200F.

 

[JADA]

Allison Transmission Questions

Hi,
I have a V730 in an 84 Flx bus (6V92). It ran perfectly for 1710 miles from where we picked it up and then no problems for a year or so then without warning, it kicks out of low to neutral when you try to drive from a dead stop. Here is what I have noticed in particular. If it is a cold takeof, it runs great. After you drive it for 8 to 10 miles, that is when the problems start. It seems when the fluid warms up is when the trouble appears to happen. I'm not sure if it has anything to do with it.
I took it in to a certified truck repair center and had the fluid changed and the transmission back flushed. I worked fine for a short period then started doing it again. Any suggestions? Is it the low pump or perhaps something to do with cooling the fluid? From least expensive to most expensive, what progression of action should I take?
Feel free to contact me via my personal email at johna@radiks.net
Thank You,
John

 

[Lolarace]

Allison Transmission Questions

Hi-
I just found this forum. I have a 02 GMC 8.1/Allison with 20k on it. To change to synthetic fluid, do I have to flush the trans, or just change the spin-on, drain the pan and refil.? Thanks
Larry

 

[jas415]

Allison Transmission Questions

We just purchased our first MH, a Monaco Diplomat, 330 HP Cummins, and a 3000 Allison. A question if you don't mind.

The temp guage on the tx hardly ever gets above 165, is that normal? It starts out at the bottom, 140 and after about 30 miles of freeway driving it gets to about 160. Outside temps here in Houston are in the mid to high 90's. The unit has about 22K miles on it and appears to have been exceptionally well maintained.

 

[Aaron]

Allison Transmission Questions

Hey allisonman! I see you have helped alot of people here! Can you try this one out for me? I have 2000 Fleetwood Discovery with a 6 speed allison. When I start the vehicle I get some eratic charging rates showing on the volt meter in the dash! First it drops to 10 volts and then shoots up to 18 volts and back and forth and so on. When I put the transmission in drive, the volt meter goes to about 15 volts and holds there. When I start driving and the trany is shifting through the gears, The voltage shown on meter seems to increase with the RPMs! As my RPMs aproach the shifting point the voltage will be over 18 volts and the Battery light comes on! Now you would think I have a battery or alternator problem going on! But! I have do the following in this order:

When the problem first started I checked the batteries,
The I replaced the alternator - no change

I put the coach into a Freightliner dealer for service, They replaced the chassis batteries and told me the alternator was most likely the problem.

I replaced the alternator again - no change

I contacted Freightliner's customer help center, They told me that the only thing that would cause overcharging is a bad ground so I have removed and cleaned all terminals, and grounds. - still no change!

So my question is do you think my voltage problem is related to the transmission in any way?

Thanks,
Aaron

 

[rbigrig]

Allison Transmission Questions

Allisonman!

First, let me say thanks for the info you are providing people here. You are an obvious font of knowledge, and it is getting people out of the shop and back on the road. I used to be a vendor of a particular kind of telecom gear, and I used to post on the web to chat with folks, but I knew my firm would have put an end to it if they could have. Thanks for doing what you do.

So, onto my issue: I have an MD3060 in my motorhome, and I recently suffered from a 12 volt electrical short on the chassis wiring side of the house. We later found a large cable that lost some of its shielding and arced against the chassis. In any case, the digital pad display went blank when the short occurred, and we had to have the driveshaft removed and then have the unit towed to a shop.

The shop, armed with the Fleetwood chassis wiring diagram, determined that the ECU was the culprit. We pulled the lid, and found the two 10 amp fuses intact, and all six relays tested OK. However, the pad was still dark and the transmission was not responsive. We found that about half of the ECU was "dead," and the shop ordered a new one for about $700. Being a component-level trained tech for years, I took the old ECU home to examine it. I pulled the board, and to my surprise, there weren't any semiconductors, custom chips, or even components on the back of the PC board! Then I found resistor R1 and what was left of capacitor C1. One of the radial leads out of C1, which appears to be a small-value picofarad cap, had been blown off what was left of the small cap.

That was it. A resistor and a cap, six Bosch relays, a PC board, and two ganged connectors. $700. I wanted to jump off a cliff. The whole shop visit, including troubleshooting, repairing the wiring, and the MCU was $2,912.00

What I want to know is: what is the value of the cap C2? I am curious to know the capacitance and voltage value, so I can replace it and keep this unit as a spare or pass it back to my shop so they can use it elsewhere. The shop offered to buy it from me if I can prove it will test out OK. Heck, I will be happy to put this one back in my RV and sell them back the new one! What am I also curious about is, why doesn't Allison repair or remanufacture these units???

Any info at all would be appreciated very much!

 

[Aaron]

Allison Transmission Questions

Hello, I believe That I may have solved my own problem! I found a bad battery in my house battery setup! It must be creating an open circuit! I will replace the battery in a day or so and find out for sure!

Aaron

 

[rt446dm]

Allison Transmission Questions

AllisonMan: I read an earlier post where you stated that if you change tire size it could result in damage to your Allison. I have an 02 Chev DM/Al with 49000 miles and I went up one size on tires at 42000 and made a 5000+ trip with 36' 5er. Tranm. did fine and no problems with the down shift. Just worried about further damage I did have the tran, reprogrammed after installing the tires. thanks

 

[jsparkes]

Allison Transmission Questions

Hi Allisonman,

I sure wished I had known about you sooner!

I have a 94' Dolphin 34ft with a 5.9 Cummins 230 engine and an Allison MD3060 transmission with 32,000 miles. The trans was serviced at around 25,000 mi. and new Dextron and filters were put in.

I brought my RV to your shop in Ridgefield last month for a shifting problem. Code was 21 12. The actual problem was when driving at approx 15mph in second gear then slowing a bit, the downshift into 1st produced somewhat of a shudder or sort of slip-catch action when re-accellerating. The shop was unable to reproduce this and after approx 4 hrs of time said they were unable to fix what they couldn't experience. I have subsequently taken the coach to a truck transmission shop for evaluation. They suggested dropping the valve body module and put in new gaskets then replacing filters and put in synthetic fluid (Transynd) hopefully solving the problem. A rebuild is $4800 and that would be the next step.(NOT)! Transmission operates normal in all other situations. I do occasionally get a hard downshift into 4th similar to others on the forum.

What would you advise as the next step?

Thanks for your help,

J Sparkes

 

[busboy]

Allison Transmission Questions

Hi Allisonman.
Looks like you're swamped with questions so I appologize for adding to the pile.
My wife and I own a 1984 Bluebird school bus with an automatic Allison transmission Model #MT643. All three drive gears are strong but there is a problem with the reverse. The reverse is really weak. If the ground is flat, I can get the bus rolling (with a bit of revving and waiting) and can work up momentum to get going; but if there is the slightest uphill or uneven ground, she won't go anywhere. I've worked on my own vehicles for years and have some mechanical knowledge (but I'm no tranny expert) and it seems like slippage to me. (When we bought the bus, it had been sitting for a year).
Three quick questions:
1.With your expertise, what might the problem be?
2. Are we looking at a new transmission, a full rebuild or just some tweaking and replacing problem parts?
3.Is it possible to fix this myself with the help of my father-in-law who is an old school heavy duty mechanic?

Thanks in advance for your help and insight.
Best regards,
AAron - BusBoy

 

[JADA]

Allison Transmission Questions

I sure hope someone has some suggestions 'cause I am at a total loss. I have an 84 Flx 6v92 w/Allison 730. It has been running just fine and one day I parked it and shut it down to include shutting off both battery banks (12 & 24). A couple weeks later I return and turn on the batteries, set the start switch and when I hit the start button... nothing. It was dead. My gauge indicated 3v. I realived the 12v battery switch had been turned on prior to my arrival so I assumed someone had tampered with it and drained the start batteries.
I put a 35amp charge on the battery and kicked it up to 200amps to try to start the bus and still nothing happened even though the gauge did go up to 14v.
Is there a switch that disables the starting system if the bus is shut down while in gear and the air bleeds off? Is there a way to turn the system on and then tru to start it off the starter? I don't have a clue hot to get this thing to start as I don't know what the conditiuons were when it was shut down last if in fact someone did have it running.
Should I try to put a charge on the 12v bank only? I can hear a click in the rear when the starter button is depressed. (speaking of depressed...) If anyone has any suggestions, please advise asap as I need to get the hbus started so I can take it in for some other mechanical work.
Thank you,
John Andersen III
johna@radiks.net
Topic

 

[AllisonMan]

Allison Transmission Questions

Hi ro.co3,
I am finally now able to get back on this site. You can check the temp with that connector if you have the DOC software in a computor or if you have the software loaded in a palm pilot. I have not been able to find a suitable "T" fitting for this model yet so people can install a temp sender and gauge, but I am working on it. Thanks and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Zipfrom Tenn,
Thank you for those kind words, I do this on my own time and those words are what keep me wanting to answer questions. Thank you and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Hi Trims 30,
If you get a D1 when you press the arrows, no you do not have a oil level sensor. In 95 there were not many OEM's that woulld install this.
The oil on the bottom of the case, do you have a plug on one side that feels like it has a 13mm bolt on top? It would be opposite the dipstick. If you do, I would say this is where leak is from. Allison now has an updated plug that does not leak. Thanks and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Hello TxDoc,
You should have a tow button on your vehilce and pressing this should take care of the problem. Thank you and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Hi wonttakno,
If you have a 4 stuck in your display you have a code logged. You need to have this repaired. Have you checked which code you have? You can do that by pressing both arrows either once or twice until you see D1 and followed by 4 more numbers. Write these numbers down and call your local Allison distributor or dealer to get repaired. Since this is August, you probably already know this LOL. Thanks and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Hello RVers! I am back (whether you like it or not LOL) I was kicked out of the forum and just got reinstated. I will be playing catch up for a while but I will answer all questions. Thanks and have a great day!

 

[jashields]

Allison Transmission Questions

Glad to see you back. You were missed.

 

[Norml]

Allison Transmission Questions

Allisonman,

I have a 1996 Country Coach Intrigue w/ a 300 Cummins and a 3060 Allison transmission. When the engine is cold and you shift into reverse or drive, the transmission does not engage immediately. If you rev the engine for a few seconds, reduce the rev and shift the trans, it engages immediately and smoothly. It does not happen as often when the package is at operating temperature, but it can. My local Allison dealer has looked at this problem twice and have concluded that nothing is wrong. However, I am trying to sell this motorhome and while I know that I have had nearly 40,000 trouble-free miles with it, a potential buyer may view this as the beginning of a serious problem. What do you think?