8hp70 heater bypass

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tfeni52355

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Caulk,
do you think removing the shutters helps? I have your replacement valve in my truck, great improvement on temp, before would go to 185 in traffic, now will sometimes hit up to 160 deg when in traffic but much better than before, will removing the shutters help in this case?
MRFREEZE57, I removed the shutters and replaced the stock thermostat with a 180 degree t'stat. I left the clutch and e-fans stock. Coolant temp runs 185 consistently unless I am pulling hills etc where it might get to 192. Never see the 200+ anymore like I had with the stock setup. Oil temps are around 200.

I highly recommend removing the shutters. It takes about 15 minutes and can be reversed if needed for cold weather. I live in South Carolina so I am going to try and run without the shutters this winter. Truck runs so much smoother and happier at 185 degrees. No pinging with 87 octane.

I am running the PPE pan and Valvoline Maxlife. Trans fluid temps are much slower to warm up but eventually get to 185. Most of the time running low 180's. I bought the CAULK bypass but have not put it in yet. Too busy with new job.

I will tow next week (22' travel trailer) and will note my temps. Then hopefully we can have before and after (when I put the byapss in) temps.
 

PCA4208

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Finally got the time to put in Caulk's valve in the transmission this weekend. Here's my thoughts on the process. There's no need to take the whole Shifter cable off, just unbolt the bracket and move out of the way. Do this with a cold engine! I moved my truck into the shade before and burned my hand on the Cat a dozen times. Get a small bowl or otherwise to catch the fluid, not worried about losing a few ounces but the mess wasn't fun. Have brake cleaner on hand for that lol.
Total install time took about an hour, most of that was trying to find my loc-tite to reinstall the driveshaft bolts. I am very happy with the results. So far the peak I have seen is 140 which is WAY better than the 190 that it was at before just driving around town.

Here are my results, maybe a 30 minute drive around town, mixed city/highway driving
Before
IMG_0072.jpg


After
IMG_0081.jpg
 

HEMIMANN

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@PCA4208 - congratulations! You just bought yourself 3/4 longer oil change life (from whatever your baseline change is, most guys around 30-35k without without a bypass). Based on the experimental oxidation life measurements documenting 1/2 oil oxidation life for every 20 degrees F above 140 degrees F. Delta T for you is 190-140 = 50F.

Remember, this is where transmission oil temp used to run at BEFORE the advent of these dumb thermostats.
 
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Wild one

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@PCA4208 - congratulations! You just bought yourself 3/4 longer oil change life (from whatever your baseline change is, most guys around 30-35k without without a bypass). Based on the experimental oxidation life measurements documenting 1/2 oil oxidation life for every 20 degrees F above 140 degrees F. Delta T for you is 190-140 = 50F.

Remember, this is where transmission oil temp used to run at BEFORE the advent of these dumb thermostats.
I've been around this planet for 61 years,and have yet to see an automatic transmission blow up from being to cold,and that included alot of years in the oil and gas field,where the young guys get in and start the truck at -40,and stick their foot through the floorboard as soon as it drops into gear,lol. But i have seen lots blow up from running to hot.
 

MRFREEZE57

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Finally got the time to put in Caulk's valve in the transmission this weekend. Here's my thoughts on the process. There's no need to take the whole Shifter cable off, just unbolt the bracket and move out of the way. Do this with a cold engine! I moved my truck into the shade before and burned my hand on the Cat a dozen times. Get a small bowl or otherwise to catch the fluid, not worried about losing a few ounces but the mess wasn't fun. Have brake cleaner on hand for that lol.
Total install time took about an hour, most of that was trying to find my loc-tite to reinstall the driveshaft bolts. I am very happy with the results. So far the peak I have seen is 140 which is WAY better than the 190 that it was at before just driving around town.

Here are my results, maybe a 30 minute drive around town, mixed city/highway driving
Before
View attachment 471335


After
View attachment 471336

It is well worth the time to install the bypass. I use to get as high as 188 deg, now when in stop and go traffic it may go up to 162 deg much more acceptable.
 

tfeni52355

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Pic of my ESIC while towing a 4000 Lb travel trailer last week.

180 degree T'stat and shutter delete.
PPE tranny pan
No Caulk Bypass - it's in the cabinet in the garage.

Even with the 180 degree T'stat and PPE pan the tranny temps get way too high for my liking. Engine is much happier though. Never saw Coolant above 192!

1633050874288.png
 

joesstripclub

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Everyone got me freaked out about Redline D6 being too slippery so I did a drain and fill with Maxlife last week. I rented a side by side and went up in to the mountains this weekend. It was fairly cool temps in the mid 60s, but the transmission never went above 150. I definitely worked the engine a bit as the oil temps hit just shy of 260 climbing the pass. This was my first time finally towing with the heater bypass installed and I am definitely happy with the results. Not sure what the trailer and SxS weighed, but I would guess 3000 to 4000 since it was a steel trailer.
 

MRFREEZE57

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Everyone got me freaked out about Redline D6 being too slippery so I did a drain and fill with Maxlife last week. I rented a side by side and went up in to the mountains this weekend. It was fairly cool temps in the mid 60s, but the transmission never went above 150. I definitely worked the engine a bit as the oil temps hit just shy of 260 climbing the pass. This was my first time finally towing with the heater bypass installed and I am definitely happy with the results. Not sure what the trailer and SxS weighed, but I would guess 3000 to 4000 since it was a steel trailer.
Just curious, what is it about the Redline D6 that you did not like? have had it in my truck for several thousand miles, don't see any issues from it.
 

joesstripclub

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Just curious, what is it about the Redline D6 that you did not like? have had it in my truck for several thousand miles, don't see any issues from it.
I really didnt have any issues with it. Every once in a while I would get what felt like a strange shift or a slight slip. Could have been an uneven road or who knows what else. Just decided it would make me feel better to swap some of it out since some people say they have issues. It only has a couple thousand miles on it so I saved it and will run it through a filter and mix it with Maxlife at my next fluid change. It could be coincidence, but it seems like my temps with the Maxlife were a bit warmer, which would support the hypothesis that D6 is pretty slick. It seemed like I was running about 10 degrees warmer around town the other day after changing fluid.
 

MRFREEZE57

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I really didnt have any issues with it. Every once in a while I would get what felt like a strange shift or a slight slip. Could have been an uneven road or who knows what else. Just decided it would make me feel better to swap some of it out since some people say they have issues. It only has a couple thousand miles on it so I saved it and will run it through a filter and mix it with Maxlife at my next fluid change. It could be coincidence, but it seems like my temps with the Maxlife were a bit warmer, which would support the hypothesis that D6 is pretty slick. It seemed like I was running about 10 degrees warmer around town the other day after changing fluid.

I did 3 drain and fills on both the Ram and the Ford Fusion with the D6 to get most of the old fluid flushed out and both vehicles shift normal. One has to wonder if the flavor of fluid for the auto trans is really that critical as many have said that the Maxlife one size fits all works just fine and at a much better price. If were to do over I think would use the maxlife and do a 3 time drain every 40k miles or so.
 

Rod Knock

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I did 3 drain and fills on both the Ram and the Ford Fusion with the D6 to get most of the old fluid flushed out and both vehicles shift normal. One has to wonder if the flavor of fluid for the auto trans is really that critical as many have said that the Maxlife one size fits all works just fine and at a much better price. If were to do over I think would use the maxlife and do a 3 time drain every 40k miles or so.
MaxLife uses the mid-tier universal additive package from Afton Chemicals, while Amsoil uses their top tier additive package along with PAO+Group III base oil. Given the close relationship between Lubrizol and RedLine, they probably use an additive package from Lubrizol, which isn't exactly known for being that good at making ATF additives. I'd say that Amsoil makes top tier ATF, then their OE line is very good, while MaxLife is a distant third, or on par with overpriced OEM fluids like Hyudai SP4-M or Lifegard 8.
 

tfeni52355

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View attachment 478498



Todays temps short run to grocery store. warmer out today
Nice! Now remove those radiator shutter slats (leave top and bottom one in) and install a 180 Degree Stat and you'll have it knocked. I live in SC as well and coolant runs 185-190 summer and 185 otherwise.
 

lAWROSA

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Nice! Now remove those radiator shutter slats (leave top and bottom one in) and install a 180 Degree Stat and you'll have it knocked. I live in SC as well and coolant runs 185-190 summer and 185 otherwise.
Im going to leave the slats for now. 180 t stat IDK... Im not sure whats in there now but maybe a 195F is anything. 180 too cool. There is a vid with a guy with the 180 stat and his temps go up regardless. But I thing he still has the slats...
 

Wild one

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Im going to leave the slats for now. 180 t stat IDK... Im not sure whats in there now but maybe a 195F is anything. 180 too cool. There is a vid with a guy with the 180 stat and his temps go up regardless. But I thing he still has the slats...
It's a 203F thermostat if your coolant temp is showing 204F .Generally with a 180 t-stat they'll run right around 185F. If you leave the mechanical fan in place you can run a 180 with-out tuning the electrical A/C fan to come on sooner . If a 180 t-stat scares you,you could hunt up a 195 t-stat,i've never ran a 195,but i'd guess it would run right around 198/200'ish.I've ran a 160 ,a 170 and a 180 t-stat,they all run right around 185F once the trucks at operating temp,but the heater output really sucks with a 160.
 

lAWROSA

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It's a 203F thermostat if your coolant temp is showing 204F .Generally with a 180 t-stat they'll run right around 185F. If you leave the mechanical fan in place you can run a 180 with-out tuning the electrical A/C fan to come on sooner . If a 180 t-stat scares you,you could hunt up a 195 t-stat,i've never ran a 195,but i'd guess it would run right around 198/200'ish.I've ran a 160 ,a 170 and a 180 t-stat,they all run right around 185F once the trucks at operating temp,but the heater output really sucks with a 160.
its actually got a clutch fan, and a electrical fan.. so???
 

Wild one

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its actually got a clutch fan, and a electrical fan.. so???
Yup,look inside the shroud ahead of the clutch fan,and you'll see it.When you do the clutch fan delete,you should tune the electrical fan to come on sooner. But if doing the clutch fan delete is something you don't want to do,you'll still run cooler with a 190/195 compared to the factory 203F thermostat,with-out any tuning to the A/C's electrical fan. I have no experience with a 195,but from the guys running one,the truck should run right around 198/200 or roughly about 5/6 degrees cooler then they run with the stock 203 thermostat.It's a good middle of the road t-stat between the stock 203 and a 180 thermostat.
 

tfeni52355

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I should have mentioned I left the existing eletric and clutch fans in place. Hemi just seems a lot happier at 185 deg and I'm not cooking that expensive Redline I am running! :)
 

BlownGP

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Nice! Now remove those radiator shutter slats (leave top and bottom one in) and install a 180 Degree Stat and you'll have it knocked. I live in SC as well and coolant runs 185-190 summer and 185 otherwise.

Yup, that's how mine is setup.

Not shutters and 180 t stat. Temps stay at 185 unless sitting a while on a hot day. They creep up to 190ish but drop back to 185 quick.

I thought have taking the crank fan but I don't see the point other I read one post a long time ago that the crank fan puts stress on the water pump and could make it fail sooner. Not sure how much of that his truck.
 
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