TH350 4WD Front Seal
 

I just fired up my new engine in my 72 Blazer for the first time - it runs great. I have a little problem, though - the front seal of the transmission is leaking. So, I can pull the engine, or I can drop the trans and transfer case. What are your opinions?

Re: TH350 4WD Front Seal
 

either way. Depends on tools and ability

If you have a transmission jack I would pull the transmission.


Note to all, any time an engine is out of a vehicle, you should replace the <$5 transmission front seal......

Re: TH350 4WD Front Seal
 

I actually did. I either got a bad seal or I damaged it...

Re: TH350 4WD Front Seal
 

I prefer to pull the case and the transmission my self, don’t have to mess with getting the motor back in the mounts, pulling the hood etc. plus if you get the transmission out on the Floor or a bench it’s easier to replace the seal as opposed to it still being in the truck( or blazer in your case) I know it sucks when stuff like this happens. A few years ago When I was putting the 350 back into my 3100 I got it all together, filled it with antifreeze only to find that one of the rear freeze plugs was cracked. Yep, pull the transfer case and and tranny replace the plug and so forth. The plug had bounced off a bolt or stud when installing the engine and I didn’t notice. I check those types of things now:lol:

Re: TH350 4WD Front Seal
 

I appreciate the sympathy. I have been so meticulous with this build. I couldn't believe it when I started it up and it was leaking. But I guess some days are like that. I'll probably get started on it Friday after work. I was leaning toward pulling the trans and transfer case, but you brought up some points I hadn't really thought about, and I really don't want to mess up my pretty new paint I worked so hard on, so I appreciate that. I have a floor jack, and my oldest son is coming over to help me.

Kind of a funny side story - yesterday as I was finishing up the last few vacuum connections and such, I was thinking, "Man, this sure is easier without a hood and fenders."

Re: TH350 4WD Front Seal
 

You got that right...sit on the tire and relax while you work. I have bruised a few ribs on a couple different occasions on the core support working on trucks.

And, don't feel alone. I have built a few projects and have had to pull motor's or transmissions back out many a time. Never for the same thing twice, but I would be ashamed to admit the number of times all together.