I received the following today off-net. I've sanitized it slightly to
protect the guilty. I hope the author will forgive me, but it's just
too good to keep under my hat. This old dragon has been flushed into
the open - it's time to spear it one last time.
Patrick
> Now this is interesting so I thought I'd pass it on.
> I just finished talking with the Owner of the largest crankshaft
> remanufacturing company in XXXXXXXXX. The owner has worked his way to
> ownership the hard way. His whole life has been crankshafts and he is
> indeed one of the best IMO. Having given him an intro, I'll move on.
> I asked him about thrust problems on 455 Olds engines. He said that he
> doesn't see that often enough to consider it a problem. The few that he
> has seen that he thinks are torque converter related he feels are in
> situations where the owners are winding motors too high. Not our
> situation. The single biggest problem is the one we all agree on and
> that is spinning the #1 or 7 rod bearings. He attributes this to the
> poor design of the big Olds oiling system. No surprise to any of us I'm
> sure.
> The surprise though is in the fact that he states that 1 out of every
> 10 big Olds crankshafts he does see has NO filet radiuses from the
> factory and it's too costly to make/restore them. I realize that this
> does absolutely nothing to help clear up our mini-controversy but I
> thought I'd pass it along.
> Later....
> I just finished a long talk with a transmission builder who's been in
> business at the same location for 27 years. He started out working for
> his father, now he's owner and his son's getting ready to come and work
> for him. When I was in the engine building business he did over 78
> transmissions for me and my customers and I had a single failure. (The
> transmission was in a car used mostly for drag racing.)
> He pretty much confirms that t-400's are harder on crankshafts than any
> other transmission. They do have a pressure regulator but it doesn't cut
> in at anywhere near what others do. This is part of the key to the
> durability of the T400, as well as being responsible for some of the
> problems they cause on any crank other than one that is exactly at spec.
>
>
> I asked him about downshifting using a kickdown switch vice using the
> shift lever. He says that manually selecting a lower gear does indeed
> engage an extra compression band and does put more stress on parts. It
> is there for "deceleration" purposes. Use the kickdown switch for
> acceleration and your transmission will be happier.
> I asked him about thrust. Like most of our transmission builders out
> there he says it's usually the fault of the crankshaft regrinder/engine
> rebuilder. He feels strongly that you will never experience a crankshaft
> failure (other than old age) by putting a rebuilt trans/converter behind
> an original, good running engine. But put a freshly rebuilt engine in
> front of an original converter/transmission combination and you will have
> a situation where most of the engine failures occur. The crankshaft
> preparation is the real key here.
> As I have said before....the highest price I've ever paid for a
> crankshaft regrind is $45-$50 plus bearings and plus the cost of the wet
> magnafluxing, usually an additional $15 for the latter. These are jobber
> prices. A Mondello prepped crank is $750. Bob Lamey pays $450 for his
> favorite shop to prep his crankshafts. These are not jobber regrinds.
> You get what you pay for really applies here.
>
--
Patrick Flowers
Mailto
atrick
The GMC Motorhome Page
http://www.gmcmotorhome.com
protect the guilty. I hope the author will forgive me, but it's just
too good to keep under my hat. This old dragon has been flushed into
the open - it's time to spear it one last time.
Patrick
> Now this is interesting so I thought I'd pass it on.
> I just finished talking with the Owner of the largest crankshaft
> remanufacturing company in XXXXXXXXX. The owner has worked his way to
> ownership the hard way. His whole life has been crankshafts and he is
> indeed one of the best IMO. Having given him an intro, I'll move on.
> I asked him about thrust problems on 455 Olds engines. He said that he
> doesn't see that often enough to consider it a problem. The few that he
> has seen that he thinks are torque converter related he feels are in
> situations where the owners are winding motors too high. Not our
> situation. The single biggest problem is the one we all agree on and
> that is spinning the #1 or 7 rod bearings. He attributes this to the
> poor design of the big Olds oiling system. No surprise to any of us I'm
> sure.
> The surprise though is in the fact that he states that 1 out of every
> 10 big Olds crankshafts he does see has NO filet radiuses from the
> factory and it's too costly to make/restore them. I realize that this
> does absolutely nothing to help clear up our mini-controversy but I
> thought I'd pass it along.
> Later....
> I just finished a long talk with a transmission builder who's been in
> business at the same location for 27 years. He started out working for
> his father, now he's owner and his son's getting ready to come and work
> for him. When I was in the engine building business he did over 78
> transmissions for me and my customers and I had a single failure. (The
> transmission was in a car used mostly for drag racing.)
> He pretty much confirms that t-400's are harder on crankshafts than any
> other transmission. They do have a pressure regulator but it doesn't cut
> in at anywhere near what others do. This is part of the key to the
> durability of the T400, as well as being responsible for some of the
> problems they cause on any crank other than one that is exactly at spec.
>
>
> I asked him about downshifting using a kickdown switch vice using the
> shift lever. He says that manually selecting a lower gear does indeed
> engage an extra compression band and does put more stress on parts. It
> is there for "deceleration" purposes. Use the kickdown switch for
> acceleration and your transmission will be happier.
> I asked him about thrust. Like most of our transmission builders out
> there he says it's usually the fault of the crankshaft regrinder/engine
> rebuilder. He feels strongly that you will never experience a crankshaft
> failure (other than old age) by putting a rebuilt trans/converter behind
> an original, good running engine. But put a freshly rebuilt engine in
> front of an original converter/transmission combination and you will have
> a situation where most of the engine failures occur. The crankshaft
> preparation is the real key here.
> As I have said before....the highest price I've ever paid for a
> crankshaft regrind is $45-$50 plus bearings and plus the cost of the wet
> magnafluxing, usually an additional $15 for the latter. These are jobber
> prices. A Mondello prepped crank is $750. Bob Lamey pays $450 for his
> favorite shop to prep his crankshafts. These are not jobber regrinds.
> You get what you pay for really applies here.
>
--
Patrick Flowers
Mailto
atrickThe GMC Motorhome Page
http://www.gmcmotorhome.com
