FireDemonSiC

Ever since I had this fresh level 3 700R4 installed into my car, It's had problems with the front seal leaking. It even blew the seal out the first time we tried to install it.

Now, I've got the car laid up at a local trans rebuilder replacing all the clutches, bands and steels since it never shifted right and also converting the valvebody to full manual. However, I have discovered the culprit of the recurring front seal leak. Yesterday I was at the shop when the builder removed the torque converter from the transmission. As soon as he tried to remove it, we both knew something wasn't right as it wouldn't come off and he had to work it with a crobar to get it off the trans. As soon as he pulled it off, you could see right away that the snout of the converter was trashed. The bushing in the trans was also beaten up pretty bad. Take a look at the attached picture. The dark area in the middle is a depression that has been worn into the snout of the torque converter, along with several smaller bands that have been worn down on both the top and bottom.

When I asked him what could have caused this, he said it was either the flexplate was warped or the snout was not properly welded on the converter.

FYI, when this trans blew the front seal out, to make sure I had covered all my bases I replaced the stock flexplate with an SFI chrome-moly flexplate, as well as RGA'd the torque converter back to the company that made it. According to the torque converter company, they SAID that they had cut it open to inspect and issued me a new one. Also, to be better safe than sorry, I told the shop that performed the install to check the snout with a micrometer for runout. They SAID they did this, but I wasn't there to witness it.

Somebody obviously dropped the ball here. The question is, where? What do all you tranny guru's think?

BTW, the torque converter company in question is ACC Performance. This was one of their "Boss Hog" torque converters.

3rdgenmaro

iTrader: (9)

What did you ever find out about this?

Having similar issues (not as bad, yet) as you with the same company.

3rdgenmaro

iTrader: (9)

I had almost the same issue with one of their 10" units. Hub cracked and nearly came off.

Do NOT buy a Boss Hog converter from ACC Performance. They are junk! Before I bought mine I searched around on them. I didnt find a lot of information good or bad. But all I have had is bad! The company that checked my converter said that I obviously didnt ask enough people because they knew they were junk. They have seen them in their shop before.

FireDemonSiC

Good to know. The really sad part is after it blew the seal out the first time, I sent the converter back to them and told them I wanted a different one to be better safe than sorry. Considering I still had front seal problems after that, I'm betting they either sent me the same one right back or I got ANOTHER bad one .

I'd also like to point out just how HORRIBLE this converter performed. Leaving from a stoplight felt like I had a 5000 stall converter in the car, I couldn't break the tires loose with the gas pedal all the way to the floor AND the fluid would consistently hit 220 - 240F on a warm day if you were getting on it a little bit. The converter I have in now is a 2400 - 2800 12" by TSI and is a night and day difference. No problem lighting the drag radials up at half throttle on dry pavement, consitent fluid temps of 150 - 180 give or take depending on ambient temp, and my 60' went from 2.3 with the ACC converter to 2.0 (Probably could have gotten 1.9 if I had done a few more passes) with NOTHING else done.

I had done a bit of reading, even asked five7kid of his opinion since he ran one of these but it looks like he was one of the lucky few.

I still have the converter boxed up next to my furnace. I am going to take it somewhere to have the snout checked for runout and post back with the results.

At this point, I am going to say yes. DO NOT buy a converter from ACC!!!

sofakingdom

iTrader: (1)

Without getting into pointless vendor-bashing:

Is the center line of the crank the same as the center line of the trans input shaft?

A VERY common QC defect in 70s blocks is, the dowel pins don't register the trans correctly to the crank. Sometimes it's the dowel pins that are off; sometimes it's the crank. If your starter has The Problem, it ESPECIALLY could be the crank. Sometimes the bell housing flange isn't even perpendicular to the crank.

What block have you got? What other (if any) weird problems do you have? Whether you are aware of a connection to the matter at hand or not.

FireDemonSiC

Here's what I can tell you:

The transmission is out of an 85-up F-Body. The block is of the 79 - 85 style 305.

After the rebuild, Using same dowel pins, same transmission casing, same block, same flexplate, same EVERYTHING (Even the same front pump!) with the exception of the bushing being replaced and the torque converter being swapped out with a different company...

I have had ZERO leaks from the front seal, and ZERO problems with this transmission other than a few unrelated valvebody quirks (Internal linkage hook broke and the 1st gear manual shift valve got stuck).

Something else worth mentioning is that this same block ran my old 700R4 and B&M holeshot converter with ZERO problems.

Also, The front pump got scored as well however the builder was able to salvage it.

3rdgenmaro

iTrader: (9)

This is the only issue I have.

97 block. 86 Transmission. Zero problems before this converter.

How do you figure it is pointless vendor bashing? Speaking from experience is not bashing. It is a warning.

When more people tell you they have had bad experiences with a company then people that had good experiences, well........

Pro Built Automatics

You should always check where the dowel pin rides in the case. These are known to elongate, from vibration & harmonics. GM only uses the front half of the dowel pin hole in the transmission case. If the dowel pin holes have been elongated, get longer dowel pins, if you cannot pull yours out a little ways and this will use the back half of the dowel pin hole (virgin) as it has not been used. Clean any dirt out of the dowel pin hole first. This will get the alignment square with the back of the crankshaft. Go down to your local hardware store and pick the dowel pins up, or go to Jegs & Summit for them. Much cheaper at the hardware store. Another thing here ALWAYS make sure you have a good ground on the motor and transmission.