I read this already: Obstruction in Transmission Dipstick Hole (https://www.foreforums.com/index.php?topic=32777.msg294755#msg294755)
I always look and inspect under my Coach to make sure nothing it dripping and nothing fell off. Well after my last trip I noticed some oil under the transmission. I have determined it to be coming from or very near the Dipstick tube end, right where the tube is installed on to the transmission.
Before my last long trip, as usual I was checking things and I had puled the dipstick out ( I should of leave it along) I usually just use the Allision Transmission pad. For what ever reson I pulled the dipstick out. Well I knew this from before, the dipstick does not go back in without gently wiggling it until it finds no ressitance and goes in. I don't know if I was not as gentle or patience this time around, I don't think so but maybe I pushed it in with some resistance and that action created the leak around the tube? Now what?
Is dealing with the dipstick is fairly easy for any Allision autorized place or should I make it big deal and make a trip top Nacogdoches, I think there is a transmssion shop there that most FT folks approve and trust?
After a 350 mil trip it lost 2 quarts, according to Allision electronic dipstick. I think I'd be just fine with a short dipstick and check it, from the side door where my engine battery door provides good enough access.
Thank you,
Al
Al,
Get a new gasket/O ring from Allison and just replace it. Been there, done that.
Clean the area really well before pulling the dipstick tube out so you don't get dirt in the transmission.
FYI, we did not pull transmission dipstick as always checked level via shift control panel.
Also, some have found that the very long unsupported dip stick tube needed mounting reinforcement in several places, especially near the point at the side of the transmission hole. Otherwise, the tube can pull out and leak at the place the tube sticks into the transmission. This needed support was highly recommended. Sometimes the top bracket holding the top of the tube needed to be lengthened from side of engine to reduce strain on the whole tube.
Brett,
Is the tube just pushed in with the gasket/O-ring?
Is the dip stick tube just pushed in, is it pressfit, no threads?
Sorry, been 14 years since I replaced mine, but a remember that it was push fitting, not threaded.
There are 2 brackets holding the tube. One at the top and one near the bottom. Remove these and the tube pulls out. There is an amount of fluid in the tube so be ready. I actually drained and replaced the fluid and filters on mine while I was at it. Replace the o ring and push it back in.
As it turned out, the tube was slightly cracked and leaking, not the seal. Good luck.
Great news. Thank you! :-)
When we bought our 03 coach in 2011 there was a leak around where the dipstick entered the transmission. Impossible to see where it was coming from as the fluid trails with the air currents. The previous ower had taken it to Cummins and they changed the seal. Foretravel recommended I take it to Cummins, they don't work on engines. Still leaked slightly after a year or two and I was going to change the seal again myself. Changing the seal is relatively easy, remove a few bolts that retain it and it slips out of the transmission. When I pulled the tube out of the transmission I found the tube cracked an inch or so above the transmission entry point. I removed the tube from the coach and welded the tube by gas welding and reinstalled. No more leak. If you change the seal and it still leaks it's not the seal, look elsewhere.
David, Thank you for sharing your experince.
One thing I am trying to decide is the oil. My transmission is not due for oil/filter change yet, not for couple of years and/or 10K or some more miles. I'll probably get it done before, but for now I was hoping just to fix the leak at the tube. When you fixed yours, did you drained the oil before removing the tube, or just let the amount of oil that needs to come out leak out of the tube as pulling it out?
I think I read someplace, if parked for a day or two tranmission oil is more in the pan. I guess there is less oils gets back and settles in to oil pan if the work can be done shortly after driving it for some miles?
Thank you,
AL
I believe that the amount of fluid in the pan is relative to the amount of fluid in the tube. In other words, the dipstick only goes so far down the tube and not into the pan to determine level of fluid. So when you pull the tube out, have a pan ready to accept a good amount of fluid. I could be wrong but I drained mine beforehand.
I don't remember if I drained fluid or changed the seal during a fluid change. Good chance I did it during a fluid change. Clean the area around where the tube goes in the transmission throughly, don't allow anything to contaminate the transmission. Changing the seal in the 4000 was easy. Changing the fluid and filters isn't bad but messy and a lot of fluid to dispose of.
My transmission is the MH4000, if you have the 3000 may be different.
The fluid level will be under the dipstick hole level.
Blue Threadlocker or NO Threadlocker?
I've watched few videos about this and none but this one mentioned about applying Blue Threadlocker:
https://youtu.be/3e0fa8Vbsow?t=881
(video starts at 14:41 / at Threadlocker) for the filter bolts.
Thank you,
Al
I didn't use Loctite when I did mine but it wouldn't hurt
Propman, I know you are repairing your dip stick
FYI: to answer you first question. Fortravels in Nacogdoches that need Allison transmission repairs are sent to
Stewart & Stevenson Power Products,
4935 Whitehurst Drive
Longview, TX 75602
903-758-5562
70 miles north, great service
David
I did not use any. And I was verrrrrrry careful on the torquing.
This evening I replaced the dip stick tube gasket, no problem. Just about 2 gal or so oil comes out. I guess that gasket gets old, there is a metal edge at the top/lip, where one could not tell if there is a metal but once remove it out and notice that the rubber is somewhat deteriorated and the metal gets exposed, hence the leak.
Thanks for the follow-up and picture. I will pay attention to that area on my coach.
By replacing the worn out Transmission Dip Stick Gasket I thought I had solved my problem, did I ? :-(
Drained the oil, installed new filters. I started to put about 2 quarts of new oil and go look to see if there is any leak. Well there was :-(. This time I removed to whole Transmission Dip Stick Tube out and moved it on to work bench. Yes there is a hair line crack and yes it was already welded or brazed once before. It was under the bracket that holds the tube in place, I guess that is why I had not noticed it before. Now What? I can weld but I am good for welding red iron, pipe fence angle iron kind of stuff. I'd love to get a new tube, in fact the short one. But for now, tomorrow, I really want to fix the tube, even if it is somewhat temporary, so I can put oil and make it drivable. JB Weld? Put my wire welder on the lowest setting, experiment on some scrap thin metal then have fait in myself and weld the oil tube?
No mater which repair route I take, I also like to wrap some kind of tape to it, I assume needs to be high heat resistant? So if it cracked again at least it will slow a leak.
Thank you,
Al
Gas brazing would be the best for that application.
Anything that has been prior repaired by brazing needs to be repaired the same. It would be in my top choices anyway. Clean and rebaze. That is what I would do. Should be no reason or need for tape, dont relying on that for your repair. Make sure that the tube is supported near the backend to the engine to prevent cracking again.
One of my primary tools I regularly use when welding is my sand blast cabinet and the water hose followed with brake cleaner (CORRECTION) DO NOT USE "BRAKE CLEANER" WHEN WELDING WITH ARGON THE MIX CAN PRODUCE PHOSGENE GAS AND CAN RESULT IN DEATH IF EXPOSED. SEE REPLY 31 . Scott
Had the same thing happen to mine as well. Allison dealer repaired it while doing a service.
Mark
Twig the pictured tube is cad plated steel and does show being brazed prior. I can honestly say Ive never seen a aluminum tube used on a oil dip stick tube. Easy to prove what it is. Magnet
Scott
Magnet Sticks
Make sure when fixed and ready to install that you are very careful to install the upper attachments such that the tube is not under a bind.
Thank you Brett. That part is relatively easy. There are 3 locations the tube is held at with pipe bracket. I may add one more. I would like to put a collar on top of the crack during the repair, but will see. I so want to set my welder to lowest setting and do this myself but, there is a shop down the road from me do this kind of stuff but he is out with family health issue. I'll probably call FT Monday too to see if they have a replacement tube. I don't have a part number.
Not good to weld over something that has been brazed. You would better using MAAP torch and brazing rod.
https://www.youtube.com/watch?v=GfsM9ytzwgw
Don't know if you do any mig/tig with argon as shielding gas but might want to rethink using brake cleaner. Poduces Phosgene gas. One whiff and youre a blowed toad.
Never seen any residue once sprayed and dried. It flashes off real fast even in low temperature. Ive also had good luck with using it on aluminum as prep rather than alcohol. Will look into it for sure today. The only for sure producer of Phosgene gas I've been aware of was galvanized steel. Always strip it with Muriatic acid which also produced Phosgene gas but a more controlled environment outside in my rocks. Galvanized steel should never be heated above its critical temperature without first being stripped. Yes tig, mig, argon, argon blend gas, helium. Always been more worried about all the exotic tungsten and Iridium tig electrodes that produce radioactive byproducts.
Scott
Sir you are correct. Been doing it for years and will never again. Thank you for bringing this to my attention. Very possible have actually saved my life.
The chemical in the brake cleaner is Tetrachloroethylene. When this chemical is exposed with excessive heat and argon (used in MIG and TIG welding) it also produces phosgene.
Scott
And i didnt know about galvanized welding dangers, thanks for the heads up. Welding in general is a full assault on the human body. I reckon a remote air hood is probably a good idea. Im struggling with the idea, frankly, about whether I should continue doing it. May be two Powermig 350's with push pull python guns coming on the market soon. Gettin too old, damnit. Sure would like to build one more boat though.
That multimatic 255 pulse machine was not on my want list but since I now have had it a year I don't want to part with it. Runs real nice. Push pull gun works perfect. Also rigged for .045 steel wire on other nozzle.
I hope you all are having a great Sunday.
I've done some preliminary cleaning to that tube using brake parts cleanning fluid. However for now it is just sitting there and I have not done anything further. I am waiting to hear from a local shop, hopefully Monday. I assume the brake parts cleanning fluid should be dried and should not cause any issues by Monday/Tuesday? Perhaps I should also clean it with just water and let it dry under Texas Sun?
Thank you,
Al
That is if your using argon. Brazing with a torch you should be okay. Probably the reason I've never had a problem with it is most of the surfaces I weld on dont collect fluid. If I was now going to tig work on it I might hit it first with a torch to flash off any liquid before applying the argon gas.