How much Gear Oil does the Transmission take?

I got the transmission out of a 2008 while it’s out I wanna swap new gear oil in it how much does one take?


If it’s the same Spicer as in a 2002, I’m pretty sure it’s 12oz. At least that’s what came out of mine.

Ok thanks, any tips on adding oil?

Pop out the plastic plug on the diff cover, fill it through that. Put the diff cover back on with blue rtv, don’t tighten it completely until it dries, then snug it down tight. I’m probably going to use 90wt in mine.

Wait until you get it on the cart. Remove the rubber plug and fill until oil starts to run out of the hole.

Ok while we are on the topic of filling transmission oil in a 2006+ car.

The original gems had the oil plug in the front. Simply removing the plug and using a oil extractor one could suck out all the gear oil.

Are you supposed to use a oil pump to push oil into the transmission via the rubber drain plug?

I’m assuming if the car is on level ground and you fill the transmission with gear oil while sitting flat and level the transmission sits at a angle in the car that 12oz is just below the rubber drain plug???

OK. Confession time. After replacing a leaking seal I refilled my transmission. The fill hole is small and not easily accessible on my 2009 eS. So I used a small length of rubber hose to ease the fill. One end in the hole and the 90 weight oil spout in the other end. Worked great until my hand slipped off the hose and I squirted it along with the oil into the transmission.
A week or so later the trans starting making a noise so I took it apart to try to retrieve the hose. The hose was now graffiti and there were several teeth missing from my ring gear.
So pay attention if you attempt the same short-cut with your fill (or use a much softer hose).

That sucks. I can’t believe a rubber hose could cause your metal gears to break? I would think the metal gears would “blend” the rubber hose like a Food Ninja. I have a Jabsco hand pump it’s a heavy weight fluid pump. It’s great for oil extraction or filling fluid into hard to reach places

I just changed the fluid in my 08 E4 a couple weeks ago. I have to be honest and say I did not measure the amount removed or the amount added. I used a power oil extraction pump (we use on our boat) to pull as much oil as possible out from the rubber drain/fill hole, then refilled until it ran out the same hole.
I must say it did not seem like it was 12oz, it seemed less but again I have not real idea.

Well that was about worthless info now that I typed it…

I have an '07, the manual for the 07 as well as the manual for 02 call for 16oz 30 weight when installing the differential new, so 12oz makes sense for a change. I’d be tempted to run 90 weight gear oil but will probably run 30 so I don’t mix. Do you guys think it’s better to use 90? Thanks!

90 is used by most of us. 30 was specified because it results in a bit more range.

It probably offers more protection, and the mixing probably doesn’t matter much. 90 sounds good. I will be using mobile 1 synthetic.


If you have it lying around, then sure, but you won’t gain anything with a gem gearbox on synthetic. They aren’t even close to being that demanding.

I do, and I know you’re right. It only has 5000 miles so it may not be necessary at all, but I’m still doing it. The 2007 gem makes a slight grinding/growl when I’m off the throttle or downhill. I figure it’s this or the axels.

Davey part of it is probably your input shaft . Putting some good grease on it and a new rubber bumper should reduce that noise .

On the motor, thanks I didn’t think of that. Do you know the best grease? How do I get the rubber piece, is that a GEM part or a GE part? Does anyone know the part number?

Honda makes a very good Spline grease that stays on . Bumper is a Gem part sold at a lot of places .

I’ve come to find the Honda grease everyone loved for splines (Honda 60) is discontinued. Many places suggest Honda assembly lube aka Honda M-77 in its place, I think I still have some Honda assembly lube and others somewhere. I also have some Castrol Optitemp 2 which is recommended for CV joints and also has moli. I imagine either would work well but both may be thinner than I’d like. The part number for the rubber bumper in the spline coupler for my 2007 is 5414407, I just ordered from cartmart. The old part number is 0313-00168.

The one I use is the Honda M-77 . Most grease is oil with a thichening agent . Problem is the heat generated from the engine will liquify the greae and it will run off . From my experience the m-77 is like a heavy paste almost like a thinner clay . I pulled my motor after 6 months and it was still there . I have found that in most cases it will quiet some of the whin out of the drive trane . And long term should significantly reduce wear between the motor and drive splines .

I think the cast of Jackass owned my Gem before me, I’ve fixed just about everything now. I got the rubber bumper and installed it with the optitemp, Noise solved, thank you! If it makes noise again I’ll put the 77 in, I believe it’s the Moly that gives it the staying power you speak of, it’s like lead. I could not find any of my assembly lube and have some on order. I rebuilt a Honda Magna when I was a teenager for a guy I used to work for. I told him it was done, I went to the bathroom and came back and Jack a guy I was working with took it for a test ride. I asked , where did the Magna go? He told me. I said I have not put oil in it yet. We could hear it riding around in the distance, It ran for well over 5 minutes revving around with just assembly lube, he was not being nice to it either. We were both really surprised and still laugh about it to this day. I found a good used motor at a salvage yard and dropped it in shortly after that.