Transmission service 66rfe

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EastWestHemi

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I broke down and ordered a Maghytec 45/545 transmission pan with the step, 2 quarts over stock. Also purchase the ATS thermal bypass delete, which I’m hoping will bring my trans temps down 20-30 degrees.

I got a great deal from Walmart on a 12 quart pack of supertech Atf4 for 4.44 per quart.

To top it off, I purchased to steel filter adapter for the spin on filter.

With the Mopar filters, it wasn’t cheap, but will make for a great of a Father’s Day morning in the garage.

I’ll post some pics when done. It’s about to be 100 degrees here for the next three months and it doesn’t freeze in the winter so I’m not concerned about the thermal bypass delete and having the tranny cooler freeze up.

My tranny consistently runs around 170-75, but when idling it runs creeps up to 190 for some reason.

After the stealership did the transmission recall and dropped the pan I hated the sloppy RTV job the guy did, tons of blowout on the sides, which worries me about blowout into the pan. Checked the level the other day and they were 3/4 quart low. I’m sure he didn’t check it at either operating temp or cold, as is prescribed on dipstick. I heard they probably just dumped the same fluid back into the tranny, which explains why it was short— I bet some spilled. Either way, since this truck needs to last I’m going to do the tranny right for piece of mind.

The PML tranny pan was the cheapest in cast aluminum and was leaning that direction, until I saw Moe’s selling the maghytec for $20 more with free shipping and no sales tax.... it was a no brainer. Thanks Moe’s

Btw— thanks Ram for my POS welded drag link. It’s focking spectacular. I’m waiting and counting the days until you put a real one on there.
 

U&A

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You planning to use the OEM spin in filter with the steel adapter?


Sent while firmly grasping my redline lubed RAM [emoji231]
 

Fitz-0518

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BTW, good friend is retiring from parts manager at our local dealer next year. Seen it all with Chrysler. The good the bad and the ugly. For their fleet customers. i.e. Ag company's that buy 10-20 trucks at a time. They carry the steel thread filter adapter for their fleet service managers. But, they will not sell over the counter.
Will not even start regarding the temp weld fix on the drag link.
 
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EastWestHemi

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Yup, I just removed the plastic nut with a large Allen wrench on the oem filter. Maybe they did that intentionally to allow people to remove it, or possibly remove it from the transmission if it doesn’t come out when taking off the filter.

If fleet customers demand it then that makes me feel better about spending $29 plus 10 for shipping on it. There are cheaper ones out there than the rev max one, but i kind of read on other forums the workmanship can be hit or miss.
 

U&A

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I think they used plastic because its cheap

And it also prevents you from ******* up your trans housing threads if you by chance cross thread it.

I just installed my metal adapter last weekend.


Sent while firmly grasping my redline lubed RAM [emoji231]
 

wgreggking

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EastWestHemi

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I finally got time to start working with the parts. I figured I would install the ATS thermal bypass delete first and drive around for a few days and see where my tranny temps are before I put on the Mag-hytec pan which may drop the temp further.

As for the install what a PITA. There is a bolt that holds the tranny lines to the tranny case. There is also a plastic holder clip up towards the engine oil pan, that is easy to unclip. I used small and medium adjustable wrench, plus a small and medium flat head screw driver. The bolt that holds the lines to the tranny case is 15mm.

I also had a small Allen wrench that I used to wiggle the damn metal clips off, once started I used the small flat head to pop those suckers loose. They suck, words don’t describe. They are covered with the plastic covers that snap on and off easily.

Each line has small green rubber gaskets that stay on the lines when you pull them out.

I screwed up putting the ATS bypass in because I thought doing the metal clips would be the hardest part so I did those first. The lines from the tranny just screw into the bypass, and with the clipped side in I started to cross thread the upper line from the tranny. I knew it was bad so I screwed around with it trying to back it out and it started again and again.... with a lot of colorful language I ended up taking the entire assembly apart to inspect my cross threaded aluminum. I didn’t push it, so only the first thread was bad, I used a sharp knife and cut the first thread off, which worked. I installed those lines first and the clipped lines second and everything went well, except I had put on and removed those damn clips too many times and one of them was stretched and no good. Luckily, the OEM clips are exactly the same so I used one of those. Clip the lines into the plastic holder under the engine before you secure the bolt near the tranny.

Btw, I had 1.5 quarts pour out on me. The lines from the cooler pour for a couple
Minutes, while one of the lines from the transmission wouldn’t quit. I got sick of it pouring all down my arm real quick. I took a small piece a rolled paper towel and stuffed it into the line to get it stopped when I eventually figured out it wasn’t going to stop on its own. This let me screw around doing the work. I got fluid down my arm numerous times and my rubber gloves were pretty much worthless.

My truck only has 12k miles. The fluid looked good in color, but there was a lot of shiny stuff in it, probably from the tranny cooler.

Drove around for 35 minutes in and town and small stint of freeway in 80 degree weather. Tranny only gets to 140 degrees, and takes 15 minutes to get there.

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EastWestHemi

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There is also a couple pics of the old one, with the thermostat in it. The ATS is straight through both sides. When I drop my pan I suspect my tranny cooler will drain out better not being closed off.
 

PatinAZ

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I recently serviced my trans, flush and filter. Well, by I, I mean the dealer. I dropped it off then picked it up later. I was not born to do be a mechanic. In my younger days I fixed stuff just enough to break them.
 
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EastWestHemi

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I can’t justify paying a shop $130 an hour when I’m still able bodied and enjoy doing it.... breaking stuff is common, it’s just how bad you break it and how you fix it
 
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EastWestHemi

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The ATS one I received was not colored at all, just polished aluminum. I dont know which one is better, although the rev max one claims to flow more than any other bypass. My temps are now 140-150, idled the other day for awhile while kid was sleeping and it topped out at 170 in 95 degree ambient temp. It use to be 170-175 and when idled during nap time top out around 190.

On a side note, the 2016 Chevy 2500 6.0 I drive at work probably doesn’t have a thermal bypass. It takes a long time to warm up and this morning on a 100 mile drive in 65 ambient temp it stayed at 125-130 the entire trip, coming home it went to 145-150 in 90 degree ambient temps.

I don’t know why ram would want to put in basically a 170 degree thermostat in their heavy duty truck transmission, they don’t even post the fuel economy numbers on the window sticker if I remember correctly
 

GsRAM

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The ATS one I received was not colored at all, just polished aluminum. I dont know which one is better, although the rev max one claims to flow more than any other bypass. My temps are now 140-150, idled the other day for awhile while kid was sleeping and it topped out at 170 in 95 degree ambient temp. It use to be 170-175 and when idled during nap time top out around 190.

On a side note, the 2016 Chevy 2500 6.0 I drive at work probably doesn’t have a thermal bypass. It takes a long time to warm up and this morning on a 100 mile drive in 65 ambient temp it stayed at 125-130 the entire trip, coming home it went to 145-150 in 90 degree ambient temps.

I don’t know why ram would want to put in basically a 170 degree thermostat in their heavy duty truck transmission, they don’t even post the fuel economy numbers on the window sticker if I remember correctly

Correct. Fuel economy shows as "n/a" on the window sticker
 

Blindsquirrel

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Not just ram on the mpgs, hd trucks are not required to display that. No crash rating on the sticker either for hd.
 

SyN

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The #1 reason I replaced the OEM Thermal By-Pass was to totally eliminate the POS valve from failing closed on me & over heating the 68RFE. Many reported cases of this happening.

It would only take a tiny bit of sludge or crud flowing to or from the cooler to get lodged within the tiny valve itself.
This could simply happen from neglected service just over a short period of time!


The lower ATF temps have just been an added benefit.
 
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EastWestHemi

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I agree.... the 1.5 quarts that came out of my lines when I changed it out had lots of shiny debris in it. I’ve read that the thermal bypass is a choke point and suspect that the fluid slowed down going through it and debris was starting to accumulate.
 

wgreggking

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Just received my ATS bypass valve. FYI, mine was the gold anodized color,with two ring snap fittings included, and what appears to be the metal nipple / hex insert for replacing the plastic factory nipple for the trans filter canister. Didn't expect that in the kit. Will install later this week or weekend. Not doing the pan /filter yet, I'm at 38K. Trans been running 170 -174 while driving, here at 3000 ft elevation, but, when I was in 111 degree outside air temps, down in Phoenix while idling, parked, tops out at 200, 202 degrees. On a side note oil pressure was at 33-34 psi idling, down there.

Install update 07/10/ 19
watched the two posted install vid's I linked to above. Here's the order I did it.
Sprayed area with brake cleaner.
Removed the forward white snap covers
Removed the wire clips with a pick and a small screwdriver.
Put a crescent wrench on the thermal body, loosened the rearward threaded fittings,with a 13/16" wrench, largest metric I had was 18mm,was too small.
Loosened the line to tranny hold down bracket,push aside. Used 15mm socket.
Pulled loose the front lines,the wire clip end.
Remove the loosened rear 13/16" nuts, out with the old T-stat.
Drained approx 1.5 qt's fluid.
New unit, installed the clip lock fittings, 1'" wrench into the new bypass, with the wire clips pre installed, as the clips will snap over the beveled tube ends.
Snapped the block over the forward line's until feeling them click in.
Carefully threaded the upper rear threaded fitting into the block. finger tight.
Followed by the lower threaded one as above.
Put the crescent wrench on the block, tightened the rear lines. 13/16" nuts, not too tight.
installed the 15mm bolt.
Final tightening the rear lines.
Snapped white lock rings on front lines.
Cleaned up with brake cleaner.
Started vehicle checked, no leaks, idled for a few minutes
Added 1 quart of ATF +4.
Took a 15 minute drive.
Took longer to reach temp of 160 -162 degrees. outside air was, 102 degrees.
Previous ran at 174 when warm, up to 200- 202 at 113 outside air.
Plan to check level tomorrow for the other half quart drained.

Estimated time under the truck about an hour
 
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EastWestHemi

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nice, I had to buy that nipple for the canister filter separate. Installed the pan last week finally.i installed the metal nipple into the trans first and tighten it up because I didn’t want a cross thread, spun filter onto it. Looks good, no leaks with the gasket. Haven’t tested out temps yet. I didn’t have a lot of time to let it drip. Some spilled, probably 6-7 quarts came out. I have since put back in 8.5 quarts and keep checking every morning when it’s at 70 degrees and I’m half way between the cold add and cold full marks. I can’t do a hot check because my trans doesn’t get to 180 anymore.

I am contemplating sometime down the line going with the expensive redline c+ oil and mixing into the atf+4 a couple times, but it’s hard to justify. Now I have brand new filters on the truck and the wear in metals have been drained from the cooler and the filter are changed, I might be able to just keep freshening the atf with the drain plug every year or two. With super tech available for 4.50 a quart the refresh would be $30.

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