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2003 duramax

The stock gauges are known for not being accurate. I have an 04 with an Edge touch screen. I have all the gauges on the screen and they show a little lower than the stock gauges. If you are having cooling issues you might want to pull the “stack” and clean it. I replaced my radiator last summer and couldn’t believe how dirty it was, I bought the truck new.
 
You can pull the grille and wash it out pretty good through the front with a pressure washer. These only have a few coolers so they're easier to clean. 210 is just fine on coolant temp. Ac probably needs a recharge.
 
I know that in park my truck will cool down to 350ish on egt. When its there I shut it down. Figure that's good enough.

And I'm driving a Ford 7.3 SD but my oil and water temps are 200-210ish idling in these temps. My A/C will be 50ish driving around and goes up to 60ish at stoplights. Infact all my cars do that.
 
TJ1978 said:
At what temp is there cause for concern? When I'm on driveline idling for 30+ in this Arizona summer of 110-115, it gets to about 200-210 and trans to about 200ish with the AC on. Seems fine to me as it's not overheating and once I get moving it drops. But... what temp should I consider shutting it off to cool or can I when stuck in line or traffic jam.
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It's not the coolant temp but the oil temp, and the turbo itself when it's glowing from working hard.
Sitting in traffic is nothing.
You are overthinking it.
If you're not pulling anything heavy, don't worry about, stop, count to 5 and shut it off.
 
I would change it, that way you know when it was done. I write the date, mileage and hours on all my filters. Orange or yellow paint pens work the best!
 
FASTEREDDIE is right on with can’t go wrong with changing it regardless - ya can not run fresh enough fluid or clean enough filter with any auto trans!
No need in wasting money but whenever in doubt change it and do it more often than the set schedule that is laid out by GM.
 
tarussell said:
FASTEREDDIE is right on with can’t go wrong with changing it regardless - ya can not run fresh enough fluid or clean enough filter with any auto trans!
No need in wasting money but whenever in doubt change it and do it more often than the set schedule that is laid out by GM.
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How much fluid will I need to put in if I'm just swapping the filter?
 
Just get that filter, install then add fluid? I don't want to do a flush or anything. Juts out a fresh transmission filter on the truck.

What fluid does Allison take? I see this debated all over diesel forums.
Example:
www.dieselplace.com

Trans fluid service -2003 w/100k miles - so confused by...

So, 100K miles on my 2003, time for fluids in the transmission to come out and new stuff goes in. I don't have an Allison trans shop near by, and I don't see me doing this myself. I tried reading the many Many MANY threads in here about what fluid to use and I am now more confused than ever...
www.dieselplace.com www.dieselplace.com


This filter is the proper one?

Amazon.com: Allison External Spin On Filter 29539579 with Allison Transmission Filter Magnet 29535617 : Automotive

Buy Allison External Spin On Filter 29539579 with Allison Transmission Filter Magnet 29535617: Transmission Filters - Amazon.com ✓ FREE DELIVERY possible on eligible purchases
a.co
 
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Recently I upgraded the trans cooler lines due to the crimping failure (common problem on my 2007.5 and others). I used Transynd 668 and Allison filter for trans service at that time - done at about 85K miles, now at 113K - all good now.
 
TJ1978 said:
Just get that filter, install then add fluid? I don't want to do a flush or anything. Juts out a fresh transmission filter on the truck.

What fluid does Allison take? I see this debated all over diesel forums.
Example:
www.dieselplace.com

Trans fluid service -2003 w/100k miles - so confused by...

So, 100K miles on my 2003, time for fluids in the transmission to come out and new stuff goes in. I don't have an Allison trans shop near by, and I don't see me doing this myself. I tried reading the many Many MANY threads in here about what fluid to use and I am now more confused than ever...
www.dieselplace.com www.dieselplace.com


This filter is the proper one?

Amazon.com: Allison External Spin On Filter 29539579 with Allison Transmission Filter Magnet 29535617 : Automotive

Buy Allison External Spin On Filter 29539579 with Allison Transmission Filter Magnet 29535617: Transmission Filters - Amazon.com ✓ FREE DELIVERY possible on eligible purchases
a.co
Click to expand...

TJ1978 said:
This is basically it?
Click to expand...
Yep and yep.
You can run Dex 3,4,5,6 whatever. Thats what gm put in it. But the CORRECT fluid, recommended by Allison is the transynd668 (old 295 spec)
 
Ok.. I have a quit a few bottles of dexIII for my TH350's so that's good. I'll mostly likely just get the Allison recommended fluid though
 
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There is an internal (pan) filter as well. I would drop the pan, get a new filter and I believe you can reuse the factory gasket, and do the double drain w the Transynd fluid. Plan on a 8-10 qts. I cant recall as I replaced my pan to a deeper unit at the time…

Zimmers 06 LLY

Got a set of my Aluminum wheels back from powder with the Duratracs mounted up....they aren’t as bright as the original finish, but they’re not flaking apart and corroded anymore either.
ck5.com ck5.com
Post 74
 
76zimmer said:
There is an internal (pan) filter as well. I would drop the pan, get a new filter and I believe you can reuse the factory gasket, and do the double drain w the Transynd fluid. Plan on a 8-10 qts. I cant recall as I replaced my pan to a deeper unit at the time…

Zimmers 06 LLY

Got a set of my Aluminum wheels back from powder with the Duratracs mounted up....they aren’t as bright as the original finish, but they’re not flaking apart and corroded anymore either.
ck5.com ck5.com
Post 74
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I've read that if the history of the transmissions filter changes especially the internal one, it's best to leave it be.

But I've read what you suggested. Fill, drive, drain fill and let it be. So I may do just the filter this time. The next oil change do the transmission as well as suggested.
 
My personal opinion, but for an '03, if you find the 295 spec oil, it is still good for this old of a transmission. The 668 is necessary for warranty concerns on anything 2020 and newer, at least that's what I have been told. We have over 20 Allison 4500RDS transmissions at work. We had to move to the new spec oil because of all of our newer units. I now buy the 668 spec oil in a 55 gallon drum.
We ran the 295 spec for years. And often see the transmission oil end up brown with a black tint before the transmission monitoring throws a light for service, as what the truck and drivers do can affect the oil life significantly.

Mobil is making a 668 spec oil, FYI.
Castrol was making Transyn, but it was 295 spec. Not sure if they pass the new spec yet.
 
I have like 8 quarts of DexIII can I just use that for the filter change this time?
 
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