2003 Malibu Transmission Cooler & Synthetic ATF
burly
04-08-2004, 02:16 AM
Since some of you are also doing some performance modifications to your 3100 3.1L V6 malibus, as well as some "spirited" driving, I'm posting my thoughts and experiences for the installation of a transmission cooler and the switch to synthetic ATF. Since the Malibu has the GM 4T40-E transmission, some preventive maintainence is in order to prevent its early demise. The 4T40-E transmission is rated at 190lb-ft of torque max engine input, which is what the 3.1L delivers in stock form. In an effort to allow for some mild performance upgrades, as well as to protect the transmission during spirited driving (such as carving those mountain roads), I am installing a transmission cooler and switching to synthetic ATF.
I purchased a B&M Hi-tek Supercooler Transmission cooler. It's rated for vehicles up to 16,000lbs GVW. I choose this manufacturer and model for several reasons. First of all, the manufacturer, B&M was recommended to me by several other people, including in one of the posts over in the engineering&technical form. Second, B&M sells some "low-pressure drop" transmission coolers, which do exactly that, they only induce a small drop in fluid pressure, critical in maintaining lubrication and operation of an automatic transmission. It also has a viscous valve control that passes through thicker ATF directly, while thinner ATF is routed through the cooling fins. The reason for this is that when ATF is cold, it is thicker, and in order to bring the fluid up to operating temperature in a timely manner, it is desirable Not to overcool it.
I choose Mobil 1 Synthetic ATF. After quite a bit of researching, and specifically, comparision between its major rival, Amsoil, I came to a decision. I can post more of the details to that comparision if you would like, but for now I'll keep it at Mobil 1 is almost as good if not as good as Amsoil's synthetic ATF, and is about $3 a quart cheaper. This is no small difference, especially when you are talking about 13-24qts of it. I am having a full flush of the system done, which includes the torque converter. A simple fluid change will only change about 4-5 qts, and the transmission actually holds 13qts. The reason I had to purchase 24qts is that the machine that allows you to flush the fluid in the torque converter is not 100% efficient, and therefore requires a bit of extra fluid to ensure that all the old fluid is flushed and only new fluid is present. The shop said it typically takes about 24qts to accomplish this, but any extra fliud they will return to me. I had to order the fluid from Advance Auto Parts. They Just started carrying it and only had 6qts in stock. It should arrive for me to pick up on Monday.
I have to arrange a time with the shop to have the work done, as I am going to have them do the tranny cooler while they have it up to do the fluid. The cooler I could do myself fairly easily, but i figure since I am having the system flushed And it will require more than 13qts with the addition of the cooler, it will need to be checked after it is filled. Since this tranny is sealed, there is no dipstick for me to check and add the correct amount accordingly after the installation of the cooler.
After the work is done, I'll post the results, cost breakdown, and my opinions of the modification. Let me know if this post is at all useful or if you have any questions!
I purchased a B&M Hi-tek Supercooler Transmission cooler. It's rated for vehicles up to 16,000lbs GVW. I choose this manufacturer and model for several reasons. First of all, the manufacturer, B&M was recommended to me by several other people, including in one of the posts over in the engineering&technical form. Second, B&M sells some "low-pressure drop" transmission coolers, which do exactly that, they only induce a small drop in fluid pressure, critical in maintaining lubrication and operation of an automatic transmission. It also has a viscous valve control that passes through thicker ATF directly, while thinner ATF is routed through the cooling fins. The reason for this is that when ATF is cold, it is thicker, and in order to bring the fluid up to operating temperature in a timely manner, it is desirable Not to overcool it.
I choose Mobil 1 Synthetic ATF. After quite a bit of researching, and specifically, comparision between its major rival, Amsoil, I came to a decision. I can post more of the details to that comparision if you would like, but for now I'll keep it at Mobil 1 is almost as good if not as good as Amsoil's synthetic ATF, and is about $3 a quart cheaper. This is no small difference, especially when you are talking about 13-24qts of it. I am having a full flush of the system done, which includes the torque converter. A simple fluid change will only change about 4-5 qts, and the transmission actually holds 13qts. The reason I had to purchase 24qts is that the machine that allows you to flush the fluid in the torque converter is not 100% efficient, and therefore requires a bit of extra fluid to ensure that all the old fluid is flushed and only new fluid is present. The shop said it typically takes about 24qts to accomplish this, but any extra fliud they will return to me. I had to order the fluid from Advance Auto Parts. They Just started carrying it and only had 6qts in stock. It should arrive for me to pick up on Monday.
I have to arrange a time with the shop to have the work done, as I am going to have them do the tranny cooler while they have it up to do the fluid. The cooler I could do myself fairly easily, but i figure since I am having the system flushed And it will require more than 13qts with the addition of the cooler, it will need to be checked after it is filled. Since this tranny is sealed, there is no dipstick for me to check and add the correct amount accordingly after the installation of the cooler.
After the work is done, I'll post the results, cost breakdown, and my opinions of the modification. Let me know if this post is at all useful or if you have any questions!
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