Tech Tips
WIX Oil filter numbers
- Standard 1/2 quart - 57099
- Optional 1-quart - 51060 (5.178" tall)
- Optional 2-quart - 51794 (7.822" tall)
GM Oil Filter Numbers
- Standard 1/2 quart - PF454
- Optional 1-quart - PF1218
- Optional 2-quart - PF932
Notes:
- These oil filters use a standard 13/16x16 tread and are not metric as some
may think. The 2-quart filter DOES NOT have an anti drain back valve
that the 1/2 quart and 1-quart do.
- NAPA filters are made by WIX.
- For WIX Warranty information review the document in the Downloads section.
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Oil Change Reset Procedure
This needs to be done each time the oils is changed, otherwise the GM OLF
(Oil Life Monitor System) can not correctly calculate the change interval.
- Turn the ignition to RUN, with the engine off.
- Fully press and release the accelerator pedal slowly three times within
five
seconds. If the CHANGE ENGINE OIL SOON message flashes, the system is
reset. However, if it stays on, it did not reset. Repeat the procedure.
- Turn the key to OFF.
If you would like a bit more information on the GM OLF there is a PDF
document in the Downloads section that
you can download.
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Workhorse Temp Gauge
The temperature gauge does not show the actual coolant temperature, but a
range of temperatures. Here are the range of temperatures in Fahrenheit and
Celsius.
>
At sea level the boiling point of water is 212°F or 100°C. But, with a
15-pound pressure cap (2.5° increase per lb of pressure) it is about 249°F or
120°C. Now add a 50/50 solution of anti-freeze and water this increases the
boiling point to 262°F or 128°C. So, if the temperature starts to climb you may
want to shut down the engine before it gets to the last white line before
the amber section.
One last thing to remember, the boiling point will drop about 2° per 1000 ft
of altitude.
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Allison 1000/2100 Transmission
The Allison transmisson requires a filter change after the first 5,000 miles.
After the initial filter chnge Allison recommends a filter change every 50,000
miles or 24 months and a fluid change every 150,000 miles or 48 months.
Because most of us will never see the MAXIMUM miles we should be changing the
filter every 2 years and the fluid every 4 years.
- Allison Transmission filter # 29539579
- WIX Transmission filter # 57701
Note
- Don't forget to clean/move the magnet from the old filter to the new
filter.
If you have a pre 2005 Allison transmission filled with Dexron III and wish
to go to a synthetic transmission fluid you have 2 choices.
- Use an Allison approved TES-295 transmission fluid.
- Castrol - TranSynd
- BP - Autran TES295
- Cognis Corp - Emgard 2805
- International Truck - Fleetrite Synthetic ATF
- ExxonMobil - Mobil Delvac Synthetic ATF
- Use Mobil 1 Synthetic ATF - Dexron III replacement
Notes:
- If you are switching from Dexron III to TranSynd you will need to do 2
complete fluid changes to get to 100% TranSynd fluid before you can go to the
extended drain intervals.
- Using Mobil 1 Synthetic ATF, the change intervals are the same as if you
use Dexron III.
- TranSynd - $30 to $45 a gallon
- Mobil 1 Synthetic ATF - $5 a qt or $20 a gallon
- It takes about 3 gallons for complete fluid change.
For more detailed information on recommended Allison fluids and chnge
intervals review the documents in the Downloads section.
6/6/2009 Update
It should be noted that Mobil has changed the label on Mobil 1
Synthetic. I suspect this due to the fact that GM has dropped the licenses for
Dexron III. See the next 2 photos and decide for yourself.
Old Label
New Label
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150,000 Mile Coolant
The 8.1L engine comes from the factory filled with a 50/50 mixture of water
& Dex Cool with a recommend change interval of 5
years or 150,000 miles. I doubt that any of us will ever see 150,000 miles in 5
years. So that means you change every 5 years or sooner. With the way an RV gets
used I think it will be sooner rather than later.
With high cost of labor ($90 to $120 per hour) I decided to change my own
coolant after 3 years. But, I wanted do the change inside my RV building and not
make a big mess. So, I devised a plan to back flush, install new coolant and not
have to remove any hoses or crawl under the rig to drain the radiator or remove
any block plugs.
PARTS:
- Prestone Flush Kit - Wal Mart - $5
- New Pressure Cap - AutoZone/Local auto parts - $10
- 3 Gallons of anti-freeze - Wal Mart -$14
Note - The 8.1L Cooling System
holds 24.5 Quarts of coolant. Therefore you will need about 3 gallons of
antifeeze to get a 50/50 mix.
- 4' of 1" plastic hose - TSC/Ace Hardware - $4
- 3' of 1/2" plastic hose - TSC/Ace Hardware - $2
- 1/2" Female water hose fitting - TSC/Ace Hardware - $2
- Oil filler adapter to fit the 1 gallon anti-freeze jug - Wal Mart - $2
- Water hose shut off - Wal Mart - $2
- A place to PROPERLY dispose of your old anti-freeze.
Note - If you plan to use Dex Cool the 50/50 ratio is probably a bit more
critical than if you use a glycol only anti-freeze.
How To: Drain & Flush
-
Install the Flushing TEE. In my case I removed the Evans heater control
valve and installed the Flushing TEE.
-
Remove the radiator cap and install the Splash tube and hose. Drop the hose
in the 5 gallon bucket.
-
Attach the shut off to the garden hose, atttach the Back-flow preventer to
the shut off, remove the cap from the Flushing Tee and attach the Back-flow
preventer to the TEE.
-
Turn on the water and open the shut off valve. The old anti-freeze should
start to flow into the 5 gallon bucket. Shut off the water and empty the
bucket. Repeat until the water is clear.
How To: Add Ant-freeze
- Attach the female hose connect to one end of the 1/2" clear tube and
attach the oil filler adapter to the other end of the clear tube.
- Open the jug of anti-freeze and attach the oil filler adapter to the jug
of ant-freeze.
- Remove the water hose from the Flushing TEE and attach the female hose
adapter to the Flushing TEE.
- Now tip the jug of anti-freeze up and squeeze it. This will force the
anti-freeze into the system and the displaced water will run out of the
radiator into the bucket.
Finish:
- Remove the Flushing TEE.
- Install the new radiator cap.
- Remove and clean the radiator overflow tank. Renisnatll the tank and add
the appropiate amount of 50/50 mix of anti-freeze.
- Start the engine and let it come up to temp. Turn the heater to hot to
circulate the water. This should purge the air in the system.
- When the engine is cool check the radiator level. Add 50/50 mix to bring
the level to the top of the radiator.
- Don't be surprised if you have add more 50/50 mix after your first trip
out do to air pockets being purged.
Notes:
- At sea level the boiling point of water is 212° F or 100° C.
- A 15-pound pressure cap (2.5° increase per lb of pressure) adds 37.5° to
raise the boiling point to 249° F or 120° C.
- Add a 50/50 solution of anti-freeze and water this increases the boiling
point to 262° F or 128° C.
- The boiling point will drop about 2° per 1000 ft of altitude.
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Alternate Method To Change The Coolant
Copied with permisson from Max Hubrich.
I looked at the radiator coolant drain plug several times over the past few
years and was always wondering why it looked like it did?? It is not like the
old metal petcock style (similiar to a small Winegard "bat wing" antenna) that
many of us dealt with over the years. I finally figured it out, and oh, by
the way, it is located on the lower left corner -- Drivers side, (engine side-
facing to the rear). My mission was to change out the coolant -- along with a
good flush. Before I go any further, I know, unless you completely
dissassemble the engine you cannot get ALL the old fluid out-- kinda like
changing transmission fluid. I wanted to see the condition of the old
coolant before I used Oemy's flush method.
First thing you need is a 1/4" drive ratchet with a 4" extension-
Here is a picture of the "little Devil" white nylon drain plug-- In the open
position-- That's coolant coming out.
Make sure the engine is cooled down -- not hot!! The 1/4" square of the 4"
ratchet extension fits into the square drain plug hole. Now, this is where you
must be extra, extra careful---
- Gently, very, very gently, turn the drain plug just a WEE BIT
counterclockwise. You will feel a little "snap"-- It is now unlocked and will
start to seep.
- Now you gently, very gently-again, turn it counterwise a little more (like
a quarter, to a half turn) and it is now fully extended--about a half inch (as
the picture shows). Go no further-- Do not try to remove it completely-- If
you do, you will be probably buying a new radiator!! I understand there is an
"O" ring inside the valve that does the sealing.
- Now move your bucket or pan under the rig and open/remove the radiator
cap. Stand back as the fluid will now gush out.
Here is what my fluid looked like---
My fluid was "sparkling clean" no debris, dirt or rust at all. After 6
refills of water, running the engine each time, with the dash board heater valve
set to the "full hot position" this is what the last drain of fluid looked
like---
When your all done, the radiator cap should be in this position. The arrows
(which I highlighted) should be parallel to the vent tube to the overflow tank.
This insures thet the cap is seated properly.
Because my old fluid was so clean I used Dex-Cool (the pink stuff) as the
refill type. A completely empty system will hold about 24 1/2 qts. I bought
three gallons (only used two) of the full strength stuff and mixed it 50/50 with
water.
It took about 4 hours to complete this coolant change because of
the run/cool process. Believe it or not, the hardest part of the whole operation
is getting the radiator cap on and off. It has two definite settings and you
must push down hard to release it from it's second locking step.
The
drain plug itself was a piece of cake! Good luck to those folks who want to "Do
it Yourself".
Max H
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100,000 Mile Spark Plugs
GM advertises that the AC Delco spark plugs or in some cases Denso spark
plugs installed in the 8.1L engine have a service life of 100,000 miles.
Although this may be true I would not leave them in the engine for that length
of time. The biggest problem is the difficulty of removing the plug wires and
spark plugs. I would suggest that if you are NOT planning on to add new
plug wires and spark plugs that you remove the plug wires and spark plugs at
about 10,000 miles and service them as follows:
- When you remove the plug wires twist the coil and boot plugs before you
remove them DO NOT pull on the wire, as it is the weakest part.
- Mark the wires and plugs so you can return them back to the cylinder they
came out of.
- Add some dielectric grease to the coil and plug boots.
- Check and re-gap the spark plugs.
- Never clean the plugs with any sort of chemical spray cleaner or
air-powered abrasive cleaner just replace them.
- Add some Never Seize to the threads.
Why replace them?
Here is a set of Denso plugs with 78,000 miles on them.
The 2 photo's show the difference in the combustion flame travel, the
platinum tips are almost gone and the gap is more than the .60. The next
photo shows the difference between new and old.
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R&R Plug Wires and Spark Plugs
Tools/Supplies:
- 5/8" Spark Plug Socket
- 3/8" to 1/2" Adapter
- 1/2" Short Extension
- 1/2" Ratchet
- Tube of Never Seize
- Tube of Dielectric grease
Using a 1/2" ratchet gives you more leverage over a 3/8" ratchet to remove
the spark plugs.
How To:
- Prep your plug wires with dielectric grease.
- Gap the plugs and add Never Seize to the threads.
- Start the engine and turn the wheels as far to the right as possible and
turn off the engine.
- Now get something to kneel on and crawl under the rig.
- Remove all the plug wires first. DO NOT pull on the plug wire. Twist the
coil boots and remove them first. Repeat with the plug boots.
- Remove the plugs
- Install the new plugs. Hand tighten and add about 1/4 turn with the
ratchet.
- Install the new wires.
- Repeat for the other side, just remember to turn the wheels to the
left.
NOTE Just in case you break a wire when you try to remove it from
the spark plug you will find that it is almost impossible to get the remaining part of
the wire off. So, how do you remove the spark plug as the broken wire is now sticking
out of the spark plug socket. Just tape a 3/4" socket to the spark plug socket
to give you an EXTRA deep plug socket.
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Brake Fluid Testing
You need to flush or replace your brake fluid:
- If it over 2 years old.
- If it boils from to much braking (heat).
- If it fails the moisture test.
- If it fails the Test Strip check (copper contaminatiom).
- All of the above!
To properly test your brake fluid you will need to check the Master
Cylinder and EACH brake caliper. The moisture tester or 100 test strips will run
about $50 each. Not something the average RV or DIY type will have in their tool
box.
The moisture tester is real easy to use. Just dip the end in brake fluid
sample, press the buttom and read the Tri-Colored LED Panel.
- Green LED = Moisture less than 1.5% (OK)
- Yellow LED = Moisture between 1.5% and 3% (Consider Flushing)
- Red Led = Moisture greater than 3% (Fluid should be flush
immediately)
- Flashing RED LED = Low battery
Using a test strip is also easy. Just dip end of the strip in a brake fluid sample and
compare the color on the strip to the colors on the test strip container.
I just changed my fluid a few prior to testing the Speed Bleeders on
7-8-2009. I had to top off the master cylinder and I am sure this skewed the
results. My test was 10. The levels are 0, 10, 30, 100, 200 & 300. 100 is
marginal and 200 or greater it's time to change.
If you think changing the fluid every 2 years is over kill, check the photo
below. This is about 1 year and less than 10,000 miles.
If you look at the photo's of the fluid it really looks bad. But, is it or is
it not still serviceable? Well, unless you have some way to test for water
content or copper contamination you will never know. I am going to error on the
side of safety and ASSUME that it is contaminated and replace it. For $20 and
less than 1 hour of my time using Speed Bleeders it is cheap cheap
cheap.
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Brake Fluid info:
- Brake fluid is gycol based.
- Brake fluid is hydroscopic - it absorbs water
- DOT 3 is all that is ever needed for normal usage.
- Ford makes a DOT 3 fluid that meets or exceeds DOT 4 specs.
- DOT 4 has a higher boiling but deteriorates faster when contaminated (so I
have been told).
- DOT 5 is silicone based and should NOT be mixed with either DOT 3 or 4
- NON contaminated fluid will either be clear or a slight amber color. The
darker it is the more the contamination.
- Gravity bleeding is the simplest method to flush and bleed the air from
the system.
- 2 Man pressure bleeding is probably the fastest.
- Vacuum bleeding works ok. See the Air Powered Bleeder entry below for more
information.
- Power bleeding using pressure and fluid replacement at the master sylinder
is the best.
Normally I would just replace the fluid with DOT 3. But, I decided to go top
shelf and use DOT 4 as it was only $1 a quart more. I bought 3 quarts and only
used 2.
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Gravity Bleed Your Brakes
Check your owners manual for any restrictions, warnings about the ABS system
and brake bleeding.
Tools/Supplies:
- 3 qts of DOT 3 or DOT 4 fluid
- 3' of plastic hose
- 3 liter clear soda bottle
- Wrench to loosen/tighten brake bleeder screw - 7/16" or 11mm
How To:
- Remove as much old brake fluid from the master cylinder reservoir and
refill with fresh fluid.
- Go to the wheel furthest from the master cylinder. Usually the passenger
side rear. Attach the plastic tube to the bleeder screw. Drop the other end in
the soda bottle that has about 1" of brake fluid in it (enough to cover the
drain tube).
- Open the bleeder valve and wait for the fluid to run. Be sure to top off
the master cylinder reservoir. Always close the bleeder valve when filling the
reservoir.
- Continue to drain the system until the fluid is clear or has a slight
amber color and there are no air bubbles.
- Repeat for the drivers side rear, pass side front and drivers side
front.
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2 Man Mwethod
The setup for this method is the same as the Gravity bleeding process except
you have someone inside the coach to pump the brake pedal to force the fluid
out.
- Read the Gravity Bleed section first for setup info, required tools and
supplies.
- Start the engine and have your inside person pump the brake pedaal and
hold it.
- Open the bleeder valve and the fluid will be forced out. The brake pedal
will go to the floor. DO NOT release the brake pedal told to by the person
bling the brakes.
- Close the bleeder valve and let the inside person that they can release
the brake pedal.
- Repeat steps 2 & 3 until the fluid runs clear.
- Refill the master cylinder reservour, move to the next caliper and repeat
steps 2 thru 5.
Note - Don't be alarmed if you see the ABS come on during the bleeding
process. This is normal and the light will go out once the brake system pressure
normalizes.
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Speed Bleeder Method
The setup for this method is the same as the Gravity bleeding process except
you install a set of Speed Bleeders first.
Now all you need to do is:
- Open the Speed Bleeder valve about 1 full turn
- Push brake pedal to the floor and realese it
- The rears take about 5-6 cycles and the fronts take about 3-4 cycles
to completely flush the lines
- Close the Speed Bleeder Screw
- Refill the master Cylinder
- Move to the next brake caliper to be flushed and repeat the process
Note - Don't be alarmed if you see the ABS come on during the bleeding
process. This is normal and the light will go out once the brake system pressure
normalizes.
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Air Powered Brake Bleeder
I decided to test an Air Powered Vacuum brake bleeder system from Griot's
Auto.
What's In The Box
Add An Air Quick Disconnect
Does it work? Well, yes but it is not what I want. It suffers from the
following:
- It takes a lot of air to create the vacuum. This is something the average
RVer probably will not have. I have a 2.5HP 230v 20 gal compressor and it ran
a lot when I pulled the fluid from the master cylinder.
- It suffers from the same problem the most vacuum systems do. You can't get
a good seal at the bleeder screw as you will draw some air in around the
threads (do to opening the bleeder) and the rubber connector after it gets
some brake fluid on it.
But, I did get the fluid changed. It took about 20 mins to empty the master
cylinder. It only took a few mins to do each wheel. But, I had to let gravity do
its job to make sure I wasn't get air in the system.
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PLEXUS Plastic Cleaner
Are you looking for nonabrasive plastic cleaner for your headlights and/or
tail lights?
- Do you have Diamond Shield installed or some other clear protection shield
on your coach?

Then Plexus is the very best you can buy. It is easy ON and easy
OFF. I ONLY use a micro fiber cloths to apply and buff.
There is only 1 Warning on the can, "Do
not use paper towels".
I have Dimond Shield installed on my coach and after about 2 applications
bugs come off with just cool water and a micro fiber cloth.
Where to Buy: Hectors Hardware $6.99
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Windsheild Wiper Refills and Renew
Finding 24" windsheild wiper refills for Dyna (made in Brazil) wiper blades
is almost impossible. The dealer wants to sell you a whole new blade for about
$25 a piece. So, I spent some time digging around the net and finally found that
NAPA has refills for the Dyna brand wiper blades.
- NAPA Part # 60-2410 - Quanity 2 per package - $7.50
While I was in the process of installing the wiper blade refills I decided to
repaint the wiper blade hardware. The paint on the wipers had faded bad.
- I used a scotch bite pad and clean them up.
- Next I used some painters tape and news paper to mask off the wipers and
windsheild.
- Next I wiped the wiper hardware down with solvent dampened lint free rag.
- Lastly I sprayed 2 coats of BBQ black paint.

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