Hi, I could use some advice from the forum members about the best way to fix an oil leak from the rear main seal. I have a V6 VS Commodore. About 12 months ago I had a coolant leak, and was told it was coming from the plate/housing on the rear of the engine. The transmission was removed and a new housing was fitted which fixed the coolant leak ($$$). However, a major oil leak has now developed which I am told is coming from the rear main seal. The transmission has to come out again to fix it. I have been quoted about $800 by the local Holden dealer (they didn't do the original job for the coolant leak). My understanding is that the new housing should have included a new seal, so what caused it to leak so soon? I don't want to be getting the transmission removed every 6-12 months so I want to try to make sure that this is fixed properly, with the best chance of success. Searching this board I saw mention of a special tool to align the housing - if this wasn't used could it have caused the leak to develop? Should I get the housing removed and re-installed to verify the alignment, rather than just installing a new seal? I asked the place that did it about the special tool and they said there is a disposable plastic tool that is now included with the parts. That didn't sound like what I had read here - is it correct? I could try to get them to fix it under warranty if they warrant their work, but (a) I'm not sure if they will, and (b) if they didn't do it right the first time, what chance they will do better the second time? I spoke to another mechanic who was recommended to me, he said about $350 to remove the transmission and put in a new seal. He suggested the seal may not have been replaced with the housing last time so it's just leaking because of age. I'm not sure whether that is likely. That's a big difference in price and I don't want to pay more than I have to, but I'd rather get it done properly than cheaply ($350 is $350 wasted if it leaks again in 6 months). Any suggestions? Thanks Andrew
if the rear housing was replaced then the seal would have been replaced as it fits in the housing, are you sure that the housing was replaced and that they did not just fix the coolant leak? Also it could be that the crank has a grove worn in it and the new seal is not sealing properly, I have heard that there is a special sleeve that you can get to put on the crank to give the seal a new surface to seal against just not sure what it is called out of interest how many K's has your car done?
The bill listed the housing in the parts list, and that is what he said he would do so I am assuming it was done. The Holden dealer mentioned the possibility of a groove in the crank, he said it happens if you don't fix the leak quickly because oil & dirt on the seal wears the crank. They will fit the sleeve (Speedy Sleeve?) if there is any sign of wear on the crank because the sleeve is very cheap compared to removing the transmission again if it still leaks. The car has about 195,000 km and is otherwise in pretty good condition.
About $180 for a houseing, gasket and rear main. The rest would be labour costs. But as stated there could be stuff on the crack that chewed the new seal. Also you need "special" tools to align the seal in the housing and when bolting to the block. These tools are like $365 from memory. I did mine 12months ago, maybe just shy of that. I did the plate gasket and the rear main, not a new plate. Mines leaking now tho.
The plate has to be aligned in two ways. It has to be concentric with the crank sealing surface and level with the sump sealing surface. A Holden dealer will have the tools (at some point anyway) to align the plate as a requirement of their franchise agreement. Yes, I'd be having the plate removed and reinstalled. The extra labour and parts for the insurance of it being correct are worth it.
I have done mine twice and a mate has done his three times. First time we did my mates, just a housing and seal and it leaked. Second time we had an alignment tool made by a tool maker and it leaked. Then I did mine with the 'updated housing and seal' (the seal has a flat lip and no garter spring) and it leaked. Then my mate did his but he drilled out the two additional bosses at the end of the sump, to make use of the two tapped holes in the housing. Took a while, but it leaked. Then I just did the sump mod in mine and the leak slowed down. In both cases the engines are serviced every 5000km and the PCV system is in good working order. I guess this is one of those times where you cannot repair a design fault. Interesting thing is that VT onwards do not suffer the same issues (or to a much lesser degree). I would assume this is partly to the different sump design.
Thanks for the advice. That is pretty much what I was thinking, I was just concerned that it would be spending money unnecessarily.
