Tranni Filter and Mobil1 Tranni Fluid

[henry davis]

> I'm thinking of converting to Mobil1 Tranni Fluid. But to do a complete
>change I will have to drill and tap the Converter. I've done this many times
>before, but not on one of these. Any advice? Has anyone converted to Mobil1
>Tranni Fluid without emptying the Converter?

Mark,

Chances are that if you let your coach sit for a while, the converter will
leak down. My 76 with 86k miles on it empties the converter in about 4 days.

Henry

 

[bdub]

I imagine a tranny filter kit will have the pan gasket included. '70's
model 425 or 400 TurboHydramatic.

Filter, Transmission
AC Delco PF-169
Atlas 131
Fram FT-1019
Motorcraft FT-19
Purolator P-219
Union B-40
Wix 51882

Final Drive, Gasket
GMC 78Z Parts Book 231285
Fei Pro RDS-55034
Victor P28883

Here's something from the GMCnet archives that might help:
- ---------------------------------------------------------------
Date: Fri, 19 Feb 1999 12:25:45 -0500
From: "Lewis Millstein"
Subject: GMC: Transmission Fluid Change

Hi All
A number of years ago in my shop I used to do changovers to B&M Trick Shift
fluid or Ford fluid in GM cars. Both were "stiffer shifting fluids" (
higher viscosity I believe with B&M highest). To accomplish this I would
disconnect the trans line at the Radiator , place a rubber tube over the
end and direct it to a clean drain pan. By cranking the engine, the old
fluid would be pumped into the drain pan. It was a start and stop process
adding new fluid
when appx. amount filled the pan. This was easiest with B&M since it was
Blue in color you could see the change, but worked with others if you
measured. Before the drain was started I would drain Fluid and change
Filter. This method worked and would enable total replacement of
transmission fluid, for a change to Synthetic.
PS fluid change from stock to B&M used to give my Customers a little more
life for their tired Transmissions.
Mark '77Palm Beach LINY
Hemogoblin's.com
- -----------------------------------------------------------------

hth
bdub

> Could someone please give me the correct part number for the tranni
>filter and gasket. I could also use the number for the final drive gasket. I
>tried a 1977 Toranado but it's not even close. Of course they could've given
>me the right box with the wrong parts.
> It's like living on the Russian Steppes here, no one has any listings
> for
>GMC parts.
> I'm thinking of converting to Mobil1 Tranni Fluid. But to do a complete
>change I will have to drill and tap the Converter. I've done this many times
>before, but not on one of these. Any advice? Has anyone converted to Mobil1
>Tranni Fluid without emptying the Converter?
>1977 403 Kingsley
>Thanks;
>Mark A

 

[bright walter]

Hi Mark,

Listen to what everyone has to say and make up your own mind. I can
tell you what I did with the GMC and other GM THM transmissions without
problem. I would not worry about the trapped fluid in the torque
converter. Keep in mind that this is not the engine, the oil is not
contaminated with combustion byproducts that acidify, etc. You can get the
same effect by changing the fluid in stages. I put the Ragusa pan on and got
4 qts of the old fluid out. At the next oil change, I changed the fluid
again and again after the next 3,000. You have 87% pure Mobil-1 by volume
running in the tranny at this point, the equivalent of 8 of the 9 or so
quarts are out at this point. I have talked to several transmission experts
and there is an opinion among them this may even be the most beneficial way
of doing the change as it gradually changes the coefficient of friction of
the oil allowing the clutches and other friction surfaces to adjust to the
new oil. If this is true I don't know, but I have had great longevity from
transmissions doing this.

So to answer your question, yes, there is at least one person out here that
did not bother to drain the torque converter and the GMC is still running
after 10,000 additional miles after making the switch to Mobil-1. Going to
do the 4th change in the next week or so, and the Mobil will be 94% pure at
that point.

Take care, walter bright, 76 GB, Delanco, NJ

- -----Original Message-----
From: Stammon [mailto:Stammon]
Sent: Thursday, June 08, 2000 11:39 PM
To: gmcmotorhome
Subject: GMC: Tranni Filter and Mobil1 Tranni Fluid


I'm thinking of converting to Mobil1 Tranni Fluid. But to do a complete
change I will have to drill and tap the Converter. I've done this many times

before, but not on one of these. Any advice? Has anyone converted to Mobil1
Tranni Fluid without emptying the Converter?
1977 403 Kingsley
Thanks;
Mark A

 

[marlene meineken]

If you can't find locally you can order the AC Delco #PF 169 from
wrenchead.com. Using as reference Oldsmobil toronodo 76. The # will come up
as TF-169 but it is the same filter. A little over $18.00. I Inquired and
this is the answer I recieved.

Hello;

Dear Sir/Madam

AC filters PF169 and TF169 are the same filter.The AC filter catolog
uses both numbers.

Herb Itkin
Automotive Technical Team
Wrenchead.com

- ----- Original Message -----
From:
To:
Sent: Thursday, June 08, 2000 8:38 PM
Subject: GMC: Tranni Filter and Mobil1 Tranni Fluid

> Could someone please give me the correct part number for the tranni
> filter and gasket. I could also use the number for the final drive gasket.
I
> tried a 1977 Toranado but it's not even close. Of course they could've
given
> me the right box with the wrong parts.
> It's like living on the Russian Steppes here, no one has any listings
for
> GMC parts.
> I'm thinking of converting to Mobil1 Tranni Fluid. But to do a
complete
> change I will have to drill and tap the Converter. I've done this many
times
> before, but not on one of these. Any advice? Has anyone converted to
Mobil1
> Tranni Fluid without emptying the Converter?
> 1977 403 Kingsley
> Thanks;
> Mark A
>