Well, those of you have read my threads lately know my getrag 5 speed is out of commission. When I tore it down I noted something especially interesting. The only vent is for the transfer case, the getrag I have doesn't appear to be vented! Bad getrag ! Does anyone out there have the chrysler product training manual for this transmission and if so is gas/vapor venting covered. Or was there a service bulletin on this? No wonder every getrag I've seen is leaking oil!

Speaking of oil, I've seen this topic covered several times. 5W30 is what is recommended for the getrag BUT, this transmission has tapered roller bearings, or common wheel bearing supporting the shafts. This is not common in manual transmission design. This is what failed in mine. Standard transmission noted that the lead countershaft bearing likes to shell out and that is what happened to mine. This creates an interesting point, wheel bearings seldom (not that I ever recall seeing) run in less than 80w90 gear oil. Now I know some will say that 80w90 thrashed thier getrag, but that defies logic for the nature of the bearing. 80w90 will cause some stiff shifting in cold weather, I owned several old chevy toploader 4 speeds over the years, 20 minute warmup in nuetral for 80w90 to shift easy in cold weather, I never had bearing trouble with one of those even in our sled pull trucks!

Interestingly the NV4500 also uses tapered roller main bearings, it uses castrol syntorq 75w140 synthetic gear lube, internally the NV4500 is strikingly similar in basic design to the getrag . The NV4500 shifts easy when cold, even at 30 below 0 F! Is anyone running 75w140 in the getrag?

 

Ive used 50 wt synthetic gear oil for a long time, it did seem to help. This is what many big rigs are running now as well.

 

The getrag has a small pocket bearing on the mainshaft that is lubed through a hole about 1/8 inch in diameter. It needs the thin oil to get in there. I have heard of people running regular gear oil and most weights in between but I prefer to stick near the factory recomendations so I've been running a 5-50 synthetic as a compromise.

 

I've been running Redline MTL in mine. It makes it shift a little better warm and a lot better cold.

 

Anybody out there figure out how the getrags vent? By the way, the vent hose off the transfer case does not vent the transmission, both units are totally sealed from one another.

Yeh, noticed the small lube hole in the mainshaft tonight when I finished teardown. I'll look back through the NV4500 information I have and see how the mainshaft oils.

 

is there any way to make that hole bigger to give it the proper lubrication? or is there something there that doesn't allow you to drill it bigger or w/e, just for the record ive never seen inside the getrag

 

I don't know if it is a wise idea to start drilling holes out quite yet. The shaft of any manual transmission is pretty darn hard alloy steel, I'll bet it is hardened as well. The only material that might cut it is an exotic metal like carbide or inconel 135. It would most likely laugh at a TiN coated drill bit.

MILLION DOLLAR QUESTION....

WHERE THE HECK IS THE GETRAGS VENT? I THINK IT WAS FORGOTTEN!

 

If I'm not mistaken, the vent is between the top cover and the main trans. case. I have a new reman. installed and am using a 5W/30 Synthetic because of the viscosity and the small oiling hole. I put in an extra 3/4 of a quart which has been suggested on previous threads. This helps lube the front bearing. It leaked oil for a few miles so I took it back to the shop and he told me it was coming out the vent and would quit.
It did quit dripping.

 

So the vent is part of the top cover? Where exactly is it? I have the top cover off in the shop so I can verify.

 

I'll look at my extra and snap some pics today..I'm wondering now, too.

 

Well, it was described to me as being in the top cover plate, at the rear, and is like a small square notch cut out of the mating surface. Now that's what he told me. I did not see it personally. BUT, I I tried to pretzel myself up to see it (while installed in truck) it seemed to be exactly like guy said. Did G1625S get any photos ? Sorry if this info is bogus. Just relating what I was told for my initial problem.

 

The only notches in the cover in have are in the sides of the sealing surface, towards the front. They are not through all the way, they are for prying the cover off with screwdrivers for service. There is a "boss" cast into the top cover next to the shifter that looks like a good spot for a vent, but no hole.

I spent the entire day today cleaning parts from the 13 years of "external lubrication" the getrag provided.

Dodge makes it, cummins breaks it , sticker coming soon!

Again, getrag , chrysler

Do you see all the getrag threads starting up all the sudden, it looks like an epidemic!

 

Is 5 quarts too much for the G360? I heard of the 1 quart overfill via the PTO cover and thought after 4.5 quarts it would start spilling out of the cover. Nothing came out so after 5 quarts I stopped.

Thanks,
Brian

 

I honestly don't know how far over 4.5 quarts a guy can go. I suppose it depends on the rake of the truck somewhat, and if you have extra cooling equipment.

Of course without a vapor vent who knows where it will leak from first, unless there is a vent?

The quest for the location of the vent on the getrag continues.

 

5 quarts is still well below the top. I run 5 quarts.