Rear main seal, should I replace it or leave it alone?

[Mike92GT]

I'm getting ready to do my clutch, flywheel, and trans swap. I figured that while I was in there I would go ahead and replace my rear main. On the other hand, I don't think it's leaking, and some folks say if it's not leaking your better off not messing with it. The engine is a DSS 308 bullet I bought new about 4 years ago. It has around 35K on it I think. What do you guys think?

 

[gt40_2003wes]

woulodnt hurt to change it i had on go out on a engine with 40k on it best to be safe.

 

[Modular2v]

if it isnt broke, dont fix it! althought some my refer to that as preventitive maint...

 

[gt40_2003wes]

why not replace if he has the money he is already in there anyways miaswell take another 45 mins and do it.

 

[tjm73]

I agree, since you are already there it'll only cost a small ammount of money and time to change it.

 

[vristang]

if it isnt broke, dont fix it! ..

I have learned this leason well. Rear mains can last a long time. The factory 302 in my 90GT never had the rear seal changed. I owned that motor for the last 100k of its life. At 4k miles I wouldn't touch pandora's box.

Just my thoughts.
jason

 

[Mavrick]

I wouldn't touch it... too many people screw it up and it haunts them!!

 

[Mike92GT]

Seems like about a 50/50 split. I guess I'll make a final decision when it's all apart and I can see for sure if it's leaking at all. The extra time/money isn't an issue, and I already have a new teflon seal just in case. I just don't want to create a leak where I didn't have one before.

 

[HISSIN50]

Mike, I am with Jason on this one. I like your thinking - check it for being supple and not vulcanized when in there. And if good, I would leave that sucker alone.

If it leaks down the line, you can fix it and not feel bad. If you swapped it now when it werent (sic) broke, and it leaks as soon as you're done, you would kick yourself (that is how I feel atleast).

Good luck.

 

[mustangjoe87]

only do it if its leaking

 

[5spd GT]

only do it if its leaking

:Word:

 

[Swarzkopf]

NO! Don't do it if it's not leaking!

You've got a 50-50 chance of the new seal leaking a bit if you change it now.

I replaced mine TWICE in the past year and it still leaks a little. I wish I never would've ****ed with it.

 

[281pony]

yep. i got a brand new shortblock from chp, rear main leaked.

dont touch it if nothing is wrong. when it starts leaking, youll want to kick your own ass. my garage floor is still pissed for the year of leaking rear main it has sitting on it.

 

[86bluecobra]

thats a hard one because you are right there but a rear main can last for 10+years before it needs to be changed. just leave it it will be fine.

 

[88GTtom]

i say if go with your gut feeling when you look at it. if you dont care about changing it again down the line, then do it. as another point tho, almost everyone has a rear main leak, so maybe you should concider yourself lucky and not ***** with it. i had mine changed and it still leaks, not as bad, but it still does...

 

[Mark89coupe]

if it isnt broke, dont fix it! althought some my refer to that as preventitive maint...

Amen to that. I did the clutch, tranny this year and didnt change the seal. I t wasnt leaking and I dont want it to