w58 extension housing

[that guy]

pix on post 4

bought a w58 and the extension housing looks like it is cracked in multiple spots. It kinda looks like broken glass that some one glued back together.
my two questions are:
could this be a casting flaw? (havent pulled the trans apart to look on the inside yet)
if it is indeed cracked what other cars did the w58 come in?
thanx for the help
chris

 

[IJ.]

Can you get a Macro pic of the "cracks"?

 

[that guy]

i can tomorrow

 

[that guy]

By loughph91, shot with DSC-W100 at 2010-02-04

By loughph91, shot with DSC-W100 at 2010-02-04

By loughph91, shot with DSC-W100 at 2010-02-04

By loughph91, shot with DSC-W100 at 2010-02-04

is this normal? pulled the trans apart today and def not all the way through
taking it to the machine shop to have the cases tanked

 

[IJ.]

Be really careful Tanking aluminium, those lines are normal and are just surface imperfections in the sand mold during casting

 

[besttrans]

Looks like just the casting.

 

[that guy]

thanx guys

 

[streetracer_258]

I think they are die cast not sand cast, but yeah just surface imperfections, mine is the same.

 

[IJ.]

If they were die cast you'd have 1000's with identical flaws, any pics/vids I've seen from Toyota have all been sand casting.

 

[streetracer_258]

Apart from the imperfections the finish seems far to smooth to be sand cast.

 

[streetracer_258]

My guess would be that the imperfections on the part are a result of wear to the die as shown below.

 

[streetracer_258]

Another picture showing how a part looks from a mould due to heat checking. Looks very similar to "that guy" third photo to me.

 

[IJ.]

Cool learnt something new thanks!

 

[streetracer_258]

No problem :bigthumb:

 

[IJ.]

Never seen the cavitation effect in a die before, the foundry I worked at as a kid was mainly sand cast though.

 

[dragracer]

Probably done using Permanent Mold process.
Most transmission cases,etc are done using this process. Especially in a high production environment.

 

[streetracer_258]

Die casting is a Permanent Mold process.

 

[dragracer]

Die casting is a Permanent Mold process.

That is correct