MMR Rear Main Seal

[JLTH2183]

I had a slow leak at my rear main seal and I finally got around to replacing it, the RPM sensor, the pulse wheel and also replaced my pilot bearing. It was not fun having to pull the trans again but if you seen my old posts I'm pretty good at doing it

Sponsored

 

[NGOT8R]

The MMR seal is far better quality than the factory seal. I installed the same kit on mine about a year ago and I’m very happy with it. One issue I ran into was mine leaked at first. I determined that the rope gasket just needed to be cut about 1/4” short on each side and RTV applied in and around both channels on the plate. I’m sure glad I discovered this before I put the tranny back in. Not sure if you encountered the same issue, but I wanted to pass the info. along before you put the tranny back.

While I was at it, I also did the MMR Head Cooling a mod. Mice mod, but very messy (coolant everywhere).

 

[NGOT8R]

@JLTH2183, I highlighted the area on the engine block in blue to show where I applied RTV, in addition to applying it in the channels on the plate as mentioned above.

 

[JLTH2183]

@JLTH2183, I highlighted the area on the engine block in blue to show where I applied RTV, in addition to applying it in the channels on the plate as mentioned above.

Yes I too applied RTV at those areas but also along the bottom where the rear main seal plate meets the oil pan. I did not cut the brown rope seal short, just flush to where it ends but I also applied some RTV in the end of the channels.

 

[NGOT8R]

Yes I too applied RTV at those areas but also along the bottom where the rear main seal plate meets the oil pan. I did not cut the brown rope seal short, just flush to where it ends but I also applied some RTV in the end of the channels.

Right on! I was hoping you‘d used RTV in those areas. I was very frustrated at first and couldn’t wrap my head around why my plate was weeping oil on both sides at the bottom, after I had installed it and sprayed everything down well with brake and parts cleaner. I came back hours later and checked to make sure all was good and noticed it had been weeping. I went through this mess twice, before I decided to cut the rope gasket and apply RTV sealer. I felt like the rope was binding up and not sealing against the lip on the oil pan. Thankfully that took care of it.

 

[Grimreaper]

Is there a need for the mmr seal holder? What short coming does it overcome?

 

[NGOT8R]

Is there a need for the mmr seal holder? What short coming does it overcome?

The MMR plate is billet aluminum and the factory plate is cast aluminum. The MMR plate is more durable and better quality which was immediately apparent to me during an actual side to side comparison.

I‘m not sure whether the MMR seal can be used with the factory plate, but if it can, it would be a good idea to do, instead of replacing it with another factory seal.

 

[TG_GT350]

@JLTH2183, I highlighted the area on the engine block in blue to show where I applied RTV, in addition to applying it in the channels on the plate as mentioned above.

Hey, what's up man,

i have a leaking rear main on my 18' gt350 and i installed the mmr rear main seal and plate. did yours leak again after you put rtv on those highlighted parts on the block?
Thanks!

 

[NGOT8R]

I struggled with it initially, but removed the plate and cut the supplied rope gasket about 3/4“ to 1” on either side and filled the channel in the plate with RTV and also applied it to the areas highlighted in blue. That should take care of it. I felt like the rope gasket was getting hung up on the back of the oil pan before that, so I got creative.

 

[TG_GT350]

I struggled with it initially, but removed the plate and cut the supplied rope gasket about 3/4“ to 1” on either side and filled the channel in the plate with RTV and also applied it to the areas highlighted in blue. That should take care of it. I felt like the rope gasket was getting hung up on the back of the oil pan before that, so I got creative.

Hey,
Great thanks,
i'll give it a shot when i redo the repair.

Sponsored