We recently acquired our '03 coupe and didn't check to see that it had no spare. The tires are basically new, but just found that the right-rear one has a large nail right in the inboard corner of the tire. Pretty sure the nail is all the way in because that tire has a slow leak.
The questions are:

If we buy two new rear tires and one cheap fulll-size wheel, do these coupes' spare tire storage area have enough space to store a full size spare tire/wheel. I don't currently have the car with me to check it out.
If so, with there being two different tire sizes on this car front and back, would it matter which size to use as the full-size spare?
Thanks!

 

A "full sized spare" is not the same tire as what's mounted on the driving wheels, it will have the same overall diameter but is typically much narrower.

Typically only vehicles equipped with a class 3 tow hitch will be OEM equipped with an actual same sized spare tire.

The spare tire size for the G should be 215/55 R17

 

So, diameter-wise, the spare tire compartment must be large enough, so are you saying the depth of our coupe's compartment isn't enough to store our 265-40-18 wheel and tire, which is what is currently on the rear axle of our car?

 

I've never tried to put the full size rear in the spare tire well, I know it's pretty tight with the OEM spare.

No idea if the tire size on your car would fit, I don't think that's an OEM tire size you listed, punch the numbers into a tire size comparison calculator and see what comes back.

 

The width of the OEM rear tires on a 6MT is 245. I pulled the full size spare out of my coupe numerous times this summer trying to diagnose my satellite radio issue, and I don't think the 245 would fit in there if you wanted the cover to fit flush.

 

I punched the numbers into a tire size calculator and the rears on your car are almost exactly 2 inches wider than the spare tire for the G. You might be able to reconfigure some of the stuff in the rear to make it work but I don't know.

https://tiresize.com/calculator/

 

OK thanks! I was just wondering if we could kill two birds with one stone.... get a spare in place and replace the bad tire with the nail. My son was planning to replace the wheels anyway but hopefully not this soon, since he just had a new clutch and exhaust put on and with a couple other repairs the car needs. Looks like I'm also going to be dropping the ps rack and suspension in the near future to replace the upper oil pan gaskets. When my son's mechanic/friend replaced the clutch, instead of just pulling the rear main seal out with a puller, he took its cover off disturbing the upper oil pan's RTV, so now the car leaks oil worse than it did. To the guy's credit, he did pull the trannie again and replaced the seal again, but it didn't fix it (no change).

 

Yeah that RMS is a pain in the *** with the upper pan in place, I did mine last year. I just used a couple large flat screwdrivers and pried the old one out. There is no "cover" for it, if it's just leaking from around the RMS then he didn't use enough Permatex Ultra Grey sealant around it. You gotta glue it in pretty good and wait a full 24 hours for the sealant to cure before you run the engine.

 

My son works for a Honda dealership, and his mechanic friend works for them and he did the whole job for a great price, but I know they did not let the RTV cure for 24 hours. I figure I'll pull the upper pan off and do it the "proper" way, according to what our Haynes manual says

But, tell me, is it possible to change the RMS donut (while the MT is out of course), without removing its surrounding "cover" that bolts to the back of the block. I'm asking because our Haynes Manual says to merely pry the RMS and then simply press/tap in the new one but says nothing about removing the surrounding cover. In a lot of cars, to remove the RMS, many people will put two screws 180 degrees apart partially into the RMS donut, then pry on the screws to pull the RMS out (there is no surrounding cover), then squarely press the new one in.

One thing I wonder about is: If a customer brings a G35 to an Infinity dealership for an oil leak from that area, does the mechanic confidently assume it's coming from the RMS? or, is the oil more likelyl coming from the bottom of the RMS cover? Is it possible for me to determine the source of the oil leak via visual inspection without removing the transmisson (or the upper oil pan)?

 

The RMS has a large flange that bolts to the back of the block, it's not just the little round seal.

Strongly recommend to use the Factory Service Manual (FSM) instead of the Haynes, the FSM is free (hosted through Nicoclub) and is much more in-depth. The document starts at FWD - Forward.

You should download all the sections for your exact vehicle and save it on your pc/phone.

https://www.nicoclub.com/infiniti-service-manuals

As for WHERE the oil is leaking, it's really only going to be valve covers or RMS, and if it's coming out of the bellhousing it's the RMS.

Fortunately it's a $25 for the OEM nissan seal, I'd recommend just getting OEM rather than an aftermarket one, your local Nissan should stock the component since it's the same on all VQ35DE motors. Or you can buy online, Z1 has the part number listed at the top of the page.

https://www.z1motorsports.com/piston...de-p-4137.html

 

EM - Engine Mechanical pages 117 has steps for removal and installation. You will probably need a gasket cutter. Page 137 has the diagram with torque values.

You should watch a couple youtube videos on people replacing the RMS for 350Z and G35 to get an idea of about how much pressure you need to put on it to pop the thing out with the upper pan installed.

 

All I know is my son took the car to his Honda mechanic/co-worker (who should have access to the Infiniti FSM) for a clutch job and to install an exhaust system. He also gave him the Fel-pro BS40631 kit which contains the RMS, retainer and upper oil-pan seal. The mechanic told him after the job was done that he did notice that the RMS was starting to seep, so he went ahead and used the Fel-pro kit. Immediately afterward, the car was leaking badly and leaving puddles in the driveway, which it wasn't doing before. My son carried it back to him, and he did the RMS job again, except they used the Infiniti OEM part that you linked, and he also replaced a cam position sensor(?) oil ring he said was leaking. However, afterward, the leak was just as bad as the first time. So, I do not believe it's the RMS donut that's leaking. I think the culprits are the upper oil-pan seal & RTV that's between the RMS retainer and the upper oil pan. Note: I changed the front brake pads last night, and nothing dripped onto the garage floor during the job, so it seems to only leak badly while the engine is running.

 

I think you need to talk with this mechanic and find out EXACTLY what he did. Did they loosen the upper pan gasket bolts to try to get the RMS out? Did they use Permatex Ultra Grey when reinstalling the RMS or did they just dry-fit the thing? Oil pan gaskets will leak like crazy, I've seen plenty of fast-dripping oil pans from a bad gasket.

I hope they didn't loosen the upper pan gasket but that's what my gut feeling is. It's a pretty significant amount of work to actually replace the whole thing. You have to use an engine bar across the top hood rails to support the weight of the engine so you can take off the crossmember (and front suspension) from below. It's a pretty time consuming repair compared to just prying the old RMS out and installing the new one with plenty of RTV.

OR the mechanic only replaced just the circular rubber ring in the middle of the RMS and didn't actually REMOVE the rear main seal. This is what the Nissan RMS looks like. This whole component should be replaced.




However I have seen a LOT of people do a half-assed job and only replace just the rubber part in the middle like at the 1:40 mark in this video.

 

Now I see that we have a difference in terminology. If you ask a typical mechanic to replace a car's RMS, he's going to think you're referring to the rear crankshaft seal (that ring that the man in the video removed). It's a very common practice to pull a cranskshaft seal in that manner or with a seal puller (a pointy hammer), and then to press/tap a new one into place over the crankshaft. Besides, how would that crankshaft seal get installed into the retainer's hole if it's not pressed into it in the first place?

I'd be willing to bet that, at the engine assembly plant, the RMS/retainer assembly was installed to the back of the block before the upper oil pan was, so they could put a bead of RTV from crankshaft seal to crankshaft seal on the upper oil pan before bolting it up. Then, the transmission would follow.

 

It's all the same terminology, you're just thinking about the style of RMS on a Chevy or Ford which is typically just a small circular seal. Every manufacturer is different, Nissan uses that larger style with it's own bolted flange housing, it's designed to be replaced as an assembly of housing+seal. The seal probably is installed before the upper oil pan during initial factory assembly but it's very common to replace them with the upper pan intact. I just did mine last year. The Nissan seals don't usually leak from the crankshaft section of the RMS it's almost always the moon gasket between the RMS housing and the upper oil pan. It's important to use a gasket cutter to get the old housing seal off because it's got Permatex ultra grey RTV sealing it to the block.

Nissan, BMW, Audi, Volkswagen, Mercedes, typically use an RMS with integrated housing.

Chevy, Toyota, Ford, Dodge, typically use just a round seal that mates directly onto the block/pan.

Check the FSM, section EM - Engine Mechanical under "removal and installation of rear oil seal" on page 117. Torque specifications are in EM - 137 Cylinder block components.

https://www.nicoclub.com/infiniti-service-manuals