Transmission leaking, found out why

[Tinwoodsman]

Where do you get the stainless steel shafts?

 

[m-35tom]

gerhard brings up a good point, the input shaft of the trans has no seal so even if the trans vent is plugged, it will still vent out the front. i wonder if it would carry any oil with it. the trans oil level is way below the shaft, but at speed lots of oil flying around. i don't see how the trans could build enough pressure to get out past the spring/ball vent on top.

tom

 

[M35A2-AZ]

You may be right!! May not need a vent, but I put one on anyway.

 

[Ord22]

The Eng, Trans, Transfer, all axles all need to breathe. it will do it thru the vents and breather tube on the eng.

 

[Ord22]

the vents are called Poppet valves. you check them once a while. To check them, push down on them and they should spring back, if not replace them. they are no good.

 

[doghead]

If you guys would read the basic operators manual and basic maintenance manuals, they tell you where the vents are located and how to maintain them.

Personal experience shows me that they all stick as they age. Removal , cleaning and lubing them is needed in any "new to you" truck.

This has been said many times by many people.

You should just read the forums for a few hours,daily until you've read it all. You can gain the Knowledge and experience of hundreds of owners, it can only make you smarter.

 

[Floridianson]

gerhard brings up a good point, the input shaft of the trans has no seal so even if the trans vent is plugged, it will still vent out the front. i wonder if it would carry any oil with it. the trans oil level is way below the shaft, but at speed lots of oil flying around. i don't see how the trans could build enough pressure to get out past the spring/ball vent on top.

tom

I do believe you and Gerhard. No need for a vent there. If you look at the fording kit it would pressurize the bellhousing that inturn will presureize the transmission and the air will escape out where it can. Most probely the rubber boot.
The transfer case now that needs a vent.

 

[MSeriesRebuild]

charles is one super great guy and really knows his stuff.. he has helped me out many times working on m37.. a very big help

Hi TIM, been awhile; always a pleasure to help; have a great one!!

 

[MSeriesRebuild]

Where do you get the stainless steel shafts?

We custom machine the ones we install.

 

[MSeriesRebuild]

gerhard brings up a good point, the input shaft of the trans has no seal so even if the trans vent is plugged, it will still vent out the front. i wonder if it would carry any oil with it. the trans oil level is way below the shaft, but at speed lots of oil flying around. i don't see how the trans could build enough pressure to get out past the spring/ball vent on top.

tom[/QUOT

There is no ball in the vent assy. Only a small spring pushing slightly upward on the external cap. It is open all the time unless foreign matter has it clogged.

 

[MSeriesRebuild]

the vents are called Poppet valves. you check them once a while. To check them, push down on them and they should spring back, if not replace them. they are no good.

99% of the vents we see that are stuck; there is nothing at all wrong with the vent itself, but rather rust and or debris has gotten in preventing to cap from popping back. Replacing is fine, but most times a thorough cleaning will accomplish the same thing and saves the cost of replacement.

 

[Troll1216]

So if I were to replace the vents on the truck and re route them would you guys go with something like: I was thinking of doing this when I do my driver side boot in prep for hurricane season.

Moeller 03343410 1/8 NPT x 3/8 Brass Baeb

 

[Flyingvan911]

Yep. That's the fitting. Barb size depends on the size of tubing you want to use.

 

[nk14zp]

gerhard brings up a good point, the input shaft of the trans has no seal so even if the trans vent is plugged, it will still vent out the front. i wonder if it would carry any oil with it. the trans oil level is way below the shaft, but at speed lots of oil flying around. i don't see how the trans could build enough pressure to get out past the spring/ball vent on top.

tom[/QUOT

There is no ball in the vent assy. Only a small spring pushing slightly upward on the external cap. It is open all the time unless foreign matter has it clogged.

There is a rubber disk the spring pushes on to seal out water.

 

[treeguy]

So to add to the venting issue . (get it?)
I've read that the fuel tank and the brake master cylinder are designed to vent into the valve cover vent tube.
My question, why are they usually disconnected and just left venting inside the engine compartment?
Also why is the valve cover vent open to the out side atmosphere and not connected in some way to the trucks air intake to burn as combustion? Isn't this how most vehicles are set up, with a PCV valve and all? This kind of set up would make sense to me but I am probably missing something. It would make the truck more water tight right?

 

[nk14zp]

Here is a pic.

 

[Floridianson]

There is a rubber disk the spring pushes on to seal out water.

Correct one way valve not open all the time.
I do believe it would be a mod. that you put in the valve when you install the fording kit. If you don't go swimming then you don't need the valve.

 

[MSeriesRebuild]

I do believe you and Gerhard. No need for a vent there. If you look at the fording kit it would pressurize the bellhousing that inturn will presureize the transmission and the air will escape out where it can. Most probely the rubber boot.
The transfer case now that needs a vent.

I respectfully disagree. The vent is needed, why? First, the shift lever boot if in good shape is sealed up pretty good, certainly beyond the point of a decent pressure relief point. That's good as you don't need oil fumes inside the cab with you. The top cover gasket used on the 3053 trans has a shield that extends back from the front interior edge of the case. This deflects direct oil splash away from the vent port on the top cover allowing free air escape while helping keep oil vapor escape to a minimum.

If the vent is obstructed; the path of least resistance then becomes through the input shaft bearing assembly and into the flywheel housing. This route is not shielded from oil splash which as you might imagine is terrific inside a transmission with spinning gears. As pressure builds and air seeks escape via the input shaft; it will carry oil with it in the form of a vapor. This can and often does over time find its way to clutch components eventually causing slipping issues as a result. What you have to realize is this isn't just a slight amount of oil that is dripping in a liquid state and finding its way out through the drain opening. Instead it is an airborne oil vapor with pressurized air as its carrier being forced into the flywheel housing. How quickly it might affect clutch components will vary based on several issues. The type or quality of the oil being used, how fast or high the pressure may build, (it's worse in hot climates) along with other issues that also come into play. With a proper functioning vent, this scenerio is totally changed. Lower quality oils will get picked up as vapor much faster than oils that have a high quality additive package blended in. Simply put, the higher end, technologically advanced oils of today will adhere and stay put where they belong much more aggressively than older spec or low quality oils will. All these things will play a big part in the bottom line result.

My opinion here is based on building many 3053 transmissions and PTO's that are typically used in conjunction with them. Experience in working with these gear boxes will bring the proper function of all the systems to light.

 

[treeguy]

My other question is that if oil is some how introduced into the bellhousing, would that allow oil to get onto the clutch and cause the clutch to slip? Esp. if you had a rear main seal leak and all the plugs in the bottom of the bellhousing?
MSeries, you beat me to the clutch issue.

 

[Flyingvan911]

I heard the military disconnected the MC and tank vent lines from the slobber tube. I wouldn't want anything to blow into the MC vent. I plan on disconnecting mine and running them in to some kind of box with a filter.