T-84 transmission vent ?

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   Hello, I have a bad leak on my T-84 transmission front seal..... on a rebuilt transmission and transfer case. Some have suggested there's a vent hole that may be plugged,.... Anyone have a good picture of where this is on the T-84? It seems like the fluid from the trans and tx case is connected between the two, could there be one on the tx case ? ?

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Garp Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 24 June 2011 Status: Offline Points: 233	Post Options Post Reply Quote Garp Report Post Thanks(0) Quote Reply Topic: T-84 transmission vent ? Posted: 14 Oct. 2015 at 3:09am
	Hello, I have a bad leak on my T-84 transmission front seal..... on a rebuilt transmission and transfer case. Some have suggested there's a vent hole that may be plugged,.... Anyone have a good picture of where this is on the T-84? It seems like the fluid from the trans and tx case is connected between the two, could there be one on the tx case ? ?

athawk11 Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 18 Jan. 2012 Location: Arvada,Colorado Status: Offline Points: 4151	Post Options Post Reply Quote athawk11 Report Post Thanks(0) Quote Reply Posted: 14 Oct. 2015 at 3:53am
	I don't know much about the T-84, but the T-90 is vented through the transfer case front bearing cap seen here in this photo. It's the copper cap.
	1- 1946 CJ2A 2- 1949 CJ3A

Garp Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 24 June 2011 Status: Offline Points: 233	Post Options Post Reply Quote Garp Report Post Thanks(0) Quote Reply Posted: 14 Oct. 2015 at 4:22pm
	OK Here's mine, I will go check that mungy looking cap on mine see if it's clogged or something....

Garp Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 24 June 2011 Status: Offline Points: 233	Post Options Post Reply Quote Garp Report Post Thanks(0) Quote Reply Posted: 14 Oct. 2015 at 9:32pm
	My cap sits pretty loose on the assembly below, and the little vent hole on the shifter column seems to have a little fluid around it, indicating it is probably venting. Still unable to find the 1 foot wide leak under the jeep every time I drive it. Been through 3 rear main seals and a new front input shaft seal on the trans. It's so bad it comes out of the inspection cover after driving 15-20 minutes.

athawk11 Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 18 Jan. 2012 Location: Arvada,Colorado Status: Offline Points: 4151	Post Options Post Reply Quote athawk11 Report Post Thanks(0) Quote Reply Posted: 14 Oct. 2015 at 10:39pm
	Garp, I remember a discussion about your rear main and how it should be positioned in the block and cap. How did you end up installing it? There is a couple other areas at the back of the engine that can leak. There is a freeze plug right behind the cam and a threaded plug. Here's a photo... Edited by athawk11 - 14 Oct. 2015 at 10:41pm
	1- 1946 CJ2A 2- 1949 CJ3A

Garp Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 24 June 2011 Status: Offline Points: 233	Post Options Post Reply Quote Garp Report Post Thanks(0) Quote Reply Posted: 15 Oct. 2015 at 4:33am
	the place that did the RMS did it three times, then finally told me maybe its coming from the input shaft on the trans.... I left it there for two weeks and he still hasn't touched it, so I took it to another shop today, guy has experience with them apparently.... so we will see if someone can find the leak instead of just throwing parts at the problem.

cpt logger Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 23 Sep. 2012 Location: Western Colorad Status: Offline Points: 3040	Post Options Post Reply Quote cpt logger Report Post Thanks(0) Quote Reply Posted: 15 Oct. 2015 at 9:27am
	What fluid is leaking out? Is it engine oil, or is it gear lube? There is no sense in changing out the rear main seal, again, if what is leaking is gear lube. It also make no sense to replace the transmission's front seal if what is leaking is engine oil. The next time you run this rig, put some kind of pan underneath the bell housing where it usually leaks from. Most folks can tell engine oil from gear lube by the smell. I can, as can most mechanics. If you find that you can not, take a sample from the pan to any mechanic & ask them what it is. While a mixture of engine oil & gear lube will smell like gear lube, if it is only engine oil, it will smell like engine oil.

johnnybravo Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 14 Feb. 2008 Location: Glen Lyn, VA Status: Offline Points: 2075	Post Options Post Reply Quote johnnybravo Report Post Thanks(0) Quote Reply Posted: 16 Oct. 2015 at 4:19am
	Remove drain plug on right (passenger) side of transmission and let it drain until it reaches a very minor drip. Replace plug. Common error to fill to completely cover cluster gear. Transmission actually operates at approx 1/3 capacity of the case. The bottom of right side drain plug hole is full. I fixed one last week with same/similar symptom. He had removed top cover and poured oil in until cluster gear was covered. Oil was expelled as you stated. PS...I suggest to use GL-1 mineral oil only (napa carries)
	Ret. USAR-Vet, 6-GPW's,, 1-M38 w/M-100, 1-47 WO "Jeep" 4X2 Wagon, several ruff CJ2&3A's, 1-CJ3B,

johnnybravo Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 14 Feb. 2008 Location: Glen Lyn, VA Status: Offline Points: 2075	Post Options Post Reply Quote johnnybravo Report Post Thanks(0) Quote Reply Posted: 16 Oct. 2015 at 4:29am
	PSS...the vent in the pics is on the transfer case. The T-84 vents around the bottom of the shifting cane. Oil coming out here is another incadiator of over full as is streaming or heavy drip after operation between transmission and bell housing. Lube does migrate between the two components. This is an easy and inexpensive procedure to try before you go into another more costly procedure.
	Ret. USAR-Vet, 6-GPW's,, 1-M38 w/M-100, 1-47 WO "Jeep" 4X2 Wagon, several ruff CJ2&3A's, 1-CJ3B,

johnnybravo Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 14 Feb. 2008 Location: Glen Lyn, VA Status: Offline Points: 2075	Post Options Post Reply Quote johnnybravo Report Post Thanks(0) Quote Reply Posted: 16 Oct. 2015 at 1:48pm
	Pass...I forgot last night but the early T-84 has the full/drain plug hole on right, same side as transfer caseand the later model has on left side of case, opposite side from transfer case. The case is still interchangeable but left side, opposite transfer case is easier to access.
	Ret. USAR-Vet, 6-GPW's,, 1-M38 w/M-100, 1-47 WO "Jeep" 4X2 Wagon, several ruff CJ2&3A's, 1-CJ3B,

tamnalan Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 08 Oct. 2013 Location: Port Orford, OR Status: Offline Points: 989	Post Options Post Reply Quote tamnalan Report Post Thanks(0) Quote Reply Posted: 17 Oct. 2015 at 12:26am
	the T84 has a nasty habit of oil migrating past the mainshaft bearing and seal from the transfer case into the transmission at highway speeds. It then pukes out the front through the bellhousing and can also come out around the shifter. The preferred G503 forum fix is to use a 307FF sealed bearing for the mainshaft and to also seal the transmission mainshaft splines with silicone before installing the mainshaft gear into the transfer case. A quick, low buck solution is to replace the transfer case and transmission fill plugs with elbow fittings and run a flexible hose between them. The migrating oil can then just flow back into the transfer case. I have this hose on my jeep. It works! Edited by tamnalan - 17 Oct. 2015 at 12:29am
	Alan Johnson 1942 MB - "TBD" 1943 MB - "Lt Bob" 1950 cj3a M-100 x2 teardrop camper: https://forums.g503.com/viewtopic.php?f=141&t=201740

Garp Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 24 June 2011 Status: Offline Points: 233	Post Options Post Reply Quote Garp Report Post Thanks(0) Quote Reply Posted: 19 Oct. 2015 at 7:10pm
	Would you happen to have any part numbers for those elbows, or a link to a page with the info?? I assume some strong hose and clamps would do the trick between them.

tamnalan Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 08 Oct. 2013 Location: Port Orford, OR Status: Offline Points: 989	Post Options Post Reply Quote tamnalan Report Post Thanks(0) Quote Reply Posted: 20 Oct. 2015 at 1:34am
	It's a (I think 1/2") pipe thread elbow fitting with barbed outlet that looks like this: . I got them at Home Depot for about $4 each. I also got about 2 feet of heavy plastic clear tubing with a white fiber reinforcement. I finished with regular Gates clamps like used for radiator hose. There's no pressure to worry about and not that much heat either. Just take a filler plug to the hardware store and match the thread size. The transfer case & transmission fill plugs are the same size. I flipped the skid plate bolt so it wouldn't chafe the tubing. Edited by tamnalan - 20 Oct. 2015 at 1:37am
	Alan Johnson 1942 MB - "TBD" 1943 MB - "Lt Bob" 1950 cj3a M-100 x2 teardrop camper: https://forums.g503.com/viewtopic.php?f=141&t=201740

Garp Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 24 June 2011 Status: Offline Points: 233	Post Options Post Reply Quote Garp Report Post Thanks(0) Quote Reply Posted: 20 Oct. 2015 at 2:48am
	SWEEET, picking them up tomorrow. Can anyone possibly confirm the threads on these? The rig is at the shop and I wont be able to get the plugs in hand to bring with me. Edited by Garp - 20 Oct. 2015 at 2:01pm

Garp Members Profile Send Private Message Find Members Posts Add to Buddy List Member Joined: 24 June 2011 Status: Offline Points: 233	Post Options Post Reply Quote Garp Report Post Thanks(0) Quote Reply Posted: 29 Oct. 2015 at 1:29am
	Shop resealed the trans, got the new metal bushing in the front, did the hose by pass thing.... still leaking out the front shaft... :-(