Allison Transmission Questions

[notlost]

Allison Transmission Questions

hi
first, thanks for all the time you seem to spend on this. these forums are so helpful to so many of us.

we just picked up a new beaver patriot with an allison 4000 and cat c13.
we are having issues with the cat engine (seems to be starving for air) but i don't think you can address that, right?

since we are new to the dp world, we have tons of questions. one is that our transmission temp rises from approx 180 degrees to over 230 when we are at idle. this happens when we are travelling and come to traffic (so the coach has been running for a while) and it happened today just a few minutes from our start while we idled.is this normal? can this have ANYTHING to do with the starving engine?

thanks, in advance.
:question:

 

[AllisonMan]

Allison Transmission Questions

Hello Cobranut,
If you are going to put synthetic in you will definatly want to have the seal replaced. It is easy if you have an installer but to do it without may be difficult. If you get a new seal from an Allison distributor or dealer, it should be a new double lipped seal which should help from further leaks. The problem with having a diesel pusher is the rear seal faces towards the front of the coach. Roaddust gathers on the seal and acts like sandpaper against your yoke, this is why Allison improved to a double lip seal 1 lip for dust and the other for oil. Thanks and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Hello Airstream,
The sensor on the back of the transmission is not the speedometer signal. What it does do is sends an output signal to the Allison computor (ECU) and from there, it sends a signal out to either an Allison VIM module or in Freightliners case, anywhere they want to put their own wire connections. Once you find that connection, you should be able to see if there is a problem with it. If you had a bad output speed sensor, you would have logged a code 22-16. I would ask Freightliner for some schematics on their speedometer wiring. Thank you and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Hello Hapo,
I hope you get this before you do the overhaul. Yes you can use other fluids, the best of course would be synthetic Transynde mad by Castrol and availabe at any Allison distributor or dealer. Another option in the AT545 onlywould be any 15-40 motor oil. This actually makes the AT545 and not any other model, shift better (you should use flat brass internal filter and make sure pickup tube is correct length). Thanks and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Hello Alaskan,
Since your motothome is out of warranty, Amsoil can be used but their synthetic fluid is NOT approved by Allison and if someone out there reads this and is thinking of adding Amsoil synthetic to get their 5 yr warranty they will be void by using Amsoil. There are only 3 manufaturers that Allison approves with a TS295 approval and they may have added a few more, but I have only seen Transynde made by Castrol.If anyone is interested in the Amsoil synthetic, ask the dealer to show you the TS295 approval, he will not be able to do so. Check allisontransmission.com and click on approved oils for the up to date list.
Another thing that worries me Alaskan is what model of transmission do you have? If it a World transmission WT = MD or HD or B model, and you did not use an Allison genuine filter, beware. I have had a few brands that have to low of a micron size and what happens is there is not enough flow and it concaves in and stops the flow of fluid in the transmission, causing major transmission failure. You should see these filters, they are totally sucked into a little ball. I cannot tell you which filters they are for obvious legal reasons, but, beware.
I hope I didnt upset you but I have to let you know what you may be up against.
Thank you and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Max Power,
Looking from the back of the transmission towards the front, on the right side there is an eigth inch pipe plug. What you need to do is go to a truck parts store that carries Jake brake parts. In one of there kits is a pressure switch. This will screw into your transmission an I would use Teflon sealer and be very very careful not to overtighten this swith. The boss that the switch goes into will crack easy if overtightened. Thanks and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Hi synabar,
I hope not LOL. Those are not bolts, they are plugs with "O" rings so you can take oil pressures in each clutch. If they are not leaking, I would leave alone. You may have a bad gasket between your valve body module and the main case or something more simple. If you have an 98 or older you may have an older style dipstick plug and the oil seeps down to the bottom of the pan. The old style plug feels like it has a bolt head on it. If you have one of these and it is opposite your dipstick side in the same location, I highly recomend it be changed to new style. Thanks and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Hi BigHarts,
The first thing you need to do is contact Allison distributor or dealer with the actual model number so they can let you know what the rated max horsepower is for your transmission. Next is the cooling system. By adding horsepower to the engine, you will be adding more heat. You will need to install an additional oil to air cooler to your bus. The way to hook it up is you have a cooler out port (and if a MT643 top cooler fitting)that goes to the cooler. Then on the output of th radiator cooler, have it go to the added on air to oil cooler, then out to the external filter and then back to the transmission. Normal operating temp is 180 - 220 but most vehicles run around 170.I hope I helped out a little to save wear on your transmission. Have fun with the conversion and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Hello McBro,
You will have an HD4060 in your coach which is the bigger than an MD which the C and B series Cummins use. You can confirm this by the tag which is on the drivers side of the transmission right above the valve body module and maincase splitline.
As far as temperature goes, you are fine. Normal operating temps are 180 to 220 deg F. If by chance you do overheat, a check transmission light will illuminate on your dash at 230 deg F and at 260, your shifting will be inhibited. You are doing fine at 195 especially on a hill which will cause heat. By running in a lower gear, this will keep a little cooler. I also suggest using synthetic Transynde on your next service which will keep the heat down another 10-20 deg and synthetic will hold viscosity with heat better than DexronIII will. I hope this answers your question. Thank you and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Hello JADA,
Do you still have good reverse? If so you may have a cracked forward clutch piston which would mean time for an overhaul. V730 transmissions are pretty strongtransmissions and that is the only thing that comes to mind when you describe the problem. Please let me know if reverse is ok and I will try a different route. What happens is when the oil is warmed up. all parts inside expand with the heat and this is when the crack leaks enough pressure to cause slippage. You may also have a cut seal. I will look for reply on reverse. Thank you and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Lolarace,
First drain the fluid, then drop the pan because this holds a lot of fluid because of the recessed pan plug, drain oil out of pan and replace pan with the same rubber/metel gasket which is re-usable (do not change internal filter)then change the spin on filter and then flush the cooler well. Thanks for the question and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Hi jas415,
Monaco does an excellent job of putting the correct cooler on their vehicles. This is probably the correct temp and if you are worried, have any mechanical shop with an infrared temp gun compare the temp with your gauge by putting the gun aimed at the sender. I bet they are close and this shouldnt cost if a good shop. Thanks and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Aron,
I do not believe it is but there are always firsts. What I think is not the transmission because what is happening is as the rpms go up (towards the end of shift) this is when volts go up. I think it is related to rpm not the transmission but you need to find the problem before you do damge not only to the transmission computor, but also other electronics in your coach. I do not know Freightliners wiring so unfortunatly you will have to find a good repair shop. (other than one you have gone to already) Thanks and have a great day!

 

[mtwallet]

Allison Transmission Questions

quote:Originally posted by 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!

 

[mtwallet]

Allison Transmission Questions

Hey Allison Man, Need some Info. I own a 1994 Airsteam w/cummins
230 turbo w/ md-3000 6 speed allison transmission. Having a problem with a dash light message ( do not shift ). This has happened 3 or
4 times.It happens when I sit idling for a short time while in gear. I know I need to get it serviced, but I'd like a heads up what to expect.Any Info would be appricated.

 

[JADA]

Allison Transmission Questions

Thanks for the reply. Reverse works fine. The tranny kicks in to neutral from a dead start only after it is warm. It works fine on some days and on other days it acts up. I can say the engine is in desperate need of an oil change. Any suggestions on an oil type?
Also, now I have another problem. It appears a friend of mine attempted to move the bus to mow grass and in doing so, I think he turned it off while it was still in reverse, I say this because now when I try to start it, the reverse warning beeper goes off in the rear end of the bus and the backup lights come on. Problem is, I can't seem to shift it into neutral to or park to start it. I believe all the air has bled from the tanks. Will that keep it from being able to be shifted to park so it will start? How can I get this in to park? Do I need to charge the tanks with air from a compressor before it will shift?
I must be a real pain but I just can't seem to get any answers from other sources.
Please advise...
John

 

[AllisonMan]

Allison Transmission Questions

Hi rbigrig,
Well, to answer your question as to why it cost so much and why Allison does not re-furbish ECU's, here are my thoughts and only my opinion. To train an Allison mechanic as well as you have obviously been trained in electronics would be very hard to do. It is hard enough to train people on all of the Allisons period. It has taken me 27 years to know as much as I do and if I had thrown in a degree in electonic engineering, there is no way I would know as much about Allisons as I know today. I am not trying to sound rude bigrig I'm just trying to explain. Wow, I just read above and I sound rude but I'm a pretty nice guy LOL.
As far as refurbishing the ECU's, I am sure someday, some company out there, maybe you, could start one which if you do I'd love to get your number LOL. I am the one who usually has to tell the customer how much the ECU's are and this is not my favorite thing to do. Before WTEC there were electronics called ATEC. Just recently we have been able to buy refurbished ATEC ECU's and ATEC transmissions have not been built since around 1992 (besides off highway and all ATEC is now called CEC). Allison is very proud of their transmissions and it is always better to install a genuine Allison part in my opinion than a refurbished part.
So to summon up, don't be hatin LOL I am just giving you my honest opinion.
Thank you very much for the question and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Aaron,
Did changing the battery help? I wouldn't think it would because they are supposed to be seperate from the chassis batteries. Let me know and have a great day!

 

[AllisonMan]

Allison Transmission Questions

Hello jsparks,
My suggestion would be to drop the VB module and replace the solenoid for 1st and me being here at my home, I do not have a troublshooting manual to see wexactly which one that is, but please call me at work and I will give that info to you. Was the other shop able to duplicate the shift? Did we charge full 4 hours? I also would like to talk to you about that so please call.Thanks and have a great day!

 

[AllisonMan]

Allison Transmission Questions

rt446dm,
The owner of our company has gone up one size and has had no problems either, but if you do have a failure, this could be the cause. Thanks and have a great day!