has anyone tried to add a vent to the m5od trans? itried and all i got was fluid spitting out of the vent. i have just put in my hurst and while it is awesome, it doesnt allow for venting like the stock shifter did. im not sure if it would but i would think that without a vent id blow a seal sooner or later. what i tried as drilling a small hole behind where the shifter mounts, put in a inflation tube (that you would use for filling a basketball ) slid a 8 mm i.d. hose 12" long with a air breather on it. at first all was good, but as the trans warmed up, after about 25 miles or so, it just started spitting fluid out. i pulled off the line/breather and it was full of oil. i capped it off and this morning when i checked the oil level i got a hissing sound like depressureazation taking place, hadnt lost much oil as some ran out with the plug out. dont know how to fix this one. i could run the line thru a jar and collect oil then just put it back in but thats silly. there has to be a way. i'll have to check out the transfer case and see if i get any ideas. my truck is a '93 dont know if they added a vent on later ones but i do know that mine has a switch on the r.h. side of the top cover that just indicates that its in nuetral, that isnt on the newer trucks, the switch for the the backup lights is on the l.h. side and is on both newer and older trans (that i have seen) maybe if i dont need that switch i could tap into that port for a vent.

 

On my '94 there's a port next to the fill plug that's unused, just another possibility.

 

well, i tried removing the neutral switch and adding my vent port there, no luck. truck didnt miss having the sensor working (i left it plugged in, but zip-tied up with the reverse light sensor wires) worked fine for about 30 minutes/25 miles but started spitting oil out the vent, which was located above the top cover. put things back the way they were and am trying it out with one of the locater dowels for the stock shift ball removed. i doubt it will work, but i guess i'll know for sure tommarrow. might rig up a guage to see how much p.s.i. im building. maybe some is tolerable, but i cant imagine so. every gearbox ive ever seen has had venting of some sort. ive been running mine without a shift boot to monitor things, its amazing how hot the trans gets, too bad i couldnt rig up a pump and cooler to circulate fluid like a automatic does.

 

Rascan, have you tried calling hurst, or the people that sold it to you ? I know your not the only one that has had this problem, I've seen threads on it before. Also ask over at rsp, they do alot of hurst installs.

 

Whoa...it shouldn't be that hot. Period. And Wendell means RPS not RSP I think.

You could try poking a hole in one of the three shift rail plugs, though I'm sure it'll leak out of there eventually. How 'bout a hole in the shifter itself similar to the stock setup?

 

im considering doing something similar to stock setup, ive also inquired at rps & rangerstation.com, removing the dowel i mentioned yesterday wasnt the answer. ive emtioned this situation to my dad, he sugested going up into the firewall, conecting to a 1" peice of pvc about a ft long, then having the breather on top of that. sounds like the next thing to try. incedently though, when i got home tonight i went to crack the fill plug to bleed off the pressure and there wasnt any. ive got so much oil underneath i cant tell whats fresh or not. think i'll do a fluid change and spray down the trans with brake clean and see where im at.

 

Well figure this. The vent in the stock transmission is through the shifter assembly. Thus, one would assume that fluid wouldn't exceed that point period (I'm definetly not getting fluid in my cab anyways...).

So in theory, you could do basically anything you want to vent it, provided that the vent is up high on the transmission and runs to a point above where the stock vent was. I'd think even a small line or similar to a breather would be plenty.

 

i wonder if its building up that much pressure to litterally spew gear oil. if the front/rear seal is still intact. not good if the front goes out and is spraying a mist of oil on the clutch. lol besides slippage it could ketch on fire i would think.

 

if it does that i think i'll hook up a vacuum line to the trans and draw air through the blown seal rather than blow oil out onto the clutch, however then i might be inhaleing trans oil into the motor. think i need to remove the top cover, tap a hole and make up a baffle over it somehow so the mainshaft isnt slinging oil directly onto it, the only thing that makes sense to me as to why my "vent trys" havent worked is that oil is being thrown onto the area im tring to vent from and as it heats up and pressure builds, that oil that has been slung onto that area by the geartrain is pushed out by the internal pressure, as long as oil is being slung there and there is internal pressure, its going to be forced out, its not a stream or even a mist, a drop will shoot out, then another, when i just had the vent hose in the cab with no breather on it, they were going as high as my console.

 

how about this. where the shifter bolts to the transmission should be raised (highest point on the transmission. and the only thing there is the shift rail. no recipricating parts. could you drill a hole in the side and tapp it out and srew in a small tube fitting then convert over to a rubber line and run it to your desired hight. this should vent the gas out. while keeping the oil in. just an idea

 

sounds like something to try, i can get fittings at work, heck i might be able to do the whole machining process during my lunch or early a.m. before my shift.

 

and if for some reason it dont work you can just cap it off.

 

Just be sure not to drill too far.