Only use a Dextron type ATF for a GM transmission.
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I found one that had this spec, hope itâs good?
Itâs going well today, when I changed the oil and filter in the box, I found a crack in the radiator, in one end, seems to go into the oil cooler hole.
GM Dexron IIIH
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As long as it says Dextron III or greater it will be fine, generics that have approval rating of Dextron is also acceptable.
I think the only insensitive GM automatic is the TH400, you could put pure hydraulic fluid in it and it will still run.
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Thanks Cody, this one was cheaper too.
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A little cleaning, now that I donât have a cooler.
Is much more crap on the left bank than the right, does it suck in different amounts?
Why does the map sensor break, have 2 broken now?
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One bank might have more baffling in the manifold than the other and it could cause soot to drop more often. Just a guess.
Jan if you donât have the radiator cooler I would suggest looking for an external cooler for the transmission.
Though in your colder area, the radiator portion actually helps warm up the transmission fluid faster and then keep it at a stable temperature.
You should avoid letting the transmission fluid get hotter than 225°F. With my stock system in my Sierra 1500 Iâve never gotten hotter than 200°F even with town traffic. In my 1976 GMC C15 I have a Radiator and External cooler but that is because I only have 3 speeds and I want to go easy on the fluid.
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Thanks for the tip, Cody I ordered a new radiator, Iâll check the temp when I get the car back up and running.
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I was thinking about whether I should do an engine flush, what is your experience with this?
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Just run it with diesel instead of oil a couple of minutes when engine is hot.
Old-time stinky diesel is better, or green/low tax, or red heating oil.
Just run it in idle/ some 2000revs, no driving, about 5 minutes, then drain.
Repeat this next oil change.
Donât do it on VW tsi/ tfsi chain engines.
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I did the Goran solution on old gunked up engines when I was a kid. Never tried it on a half way decent engine. Sometimes gunk is all that is keeping your seals from leaking. Here are some videoâs of using different clean out solutions.
https://www.google.com/search?client=firefox-b-1-d&q=project+farm++sea+foam#ip=1
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Cleaning needed for sure. 88 mbar = 35 inches. Thatâs about the highest vacuum I dare to pull on my plastic hayfilter barrel - or it will implode 
How often - or how far can you drive between cleanings?
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I have driven about 1000km (620miles) since I last cleaned.
However, there are no problems driving the car, if I hadnât had the differential meter I would probably have continued driving.
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Looking real good Jan 
Much soot, what wood you drive on?
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I almost only drive fir.
Yes, but the soot doesnât seem to release from the canvas, what was released was when I lifted the filter.
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My woodburners have problems maintaining an idle whenever I see that kind of vacuum. Thatâs when I wish I had Göranâs twin air-mix valves. 1000 km is a good number though.
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Yes, but this filter works in a different way, at idle I have almost no resistance, so there is no problem.
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Conifer trees gives a more âfattyâ soot, some old reports states more than the double amount of sticky soot when driving only conifer wood.
Maybe thats the reason?
1000km seems pretty good interval though.
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Yes, the tests that SMP did were on birch, maybe would try this, but i like spruce, because it dries so fast.
Would maybe try the filter I made first with plates instead, it might release better on these squares.
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Perhaps a filter shaker/vibrator of some kind would work if one had a soot collecting space under?
Or is it too sticky for that too
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