Today on our 2003 GMC Yukon XL, were going to install the Derale Performance Transmission Oil Cooler, part number D13504. Weve added a few additional parts to make it easier for us to install this kit through transmission line universal fittings, part number D13032 and additional hose to go from where we tap in to the manufacturers transmission line to our cooler, part number D13003. To start, weve already raised the vehicle up and were getting underneath of it. To give us some little working room, were going to go ahead and remove the rock guard for the total of five attachment points here for our rock guard. Next, well need to locate the vehicle transmission lines. These two lines here run from the radiator cooler to the transmission.
The upper line is considered the low side of the return side from our transmission cooler back to the transmission. This is the side that we prefer to tap into. Next, were going to take our tubing cutter to cut the steel line in half. Now, before I cut the line, Im going to go ahead and clean it. If we do it before we cut the line, it will prevent us from getting any of the dirt or cleaner into the transmission line.
Im going to spray a little brake cleaner and just take a rag to clean the line thoroughly. This could also be done with a piece of light grid sandpaper or emery cloth. Alright, now with the line cleaned, well go ahead and take our tubing cutter and the cut the line in half. It is recommended to use a tubing cutter as using a tubing cutter will give us a nice clean cut versus if we use a grinding wheel or a hacksaw that will leave a bunch of burst and can cause the line to become out of round. Now with my line cleaned, Ill go ahead and direct the transmission oil thats running out of the line into my drain pan.
Well let that go ahead and drain a little bit, and then well clean the line off again. When considering the orientation of way you cut your line, you want to make sure you have a straight enough section to get your compression fitting in and also enough working room that should be on the route of your hosing. Now, lets go ahead and install our compression fittings. Our new compression fitting kit will come in four pieces. Pieces will end up in this orientation.
With the compression piece or the crush piece gets smashed in between the double threaded nipple and a crush cap. Well go ahead and slide those on to the line first. Youll need to make sure that the center crush piece is lined up before you can slide it on the line. Then once its in position, well hold the double threaded nipple in position as we tighten down the crush cap. This will create our compression fitting on the line. Now that weve secured this crush sleeve in between the thread and threaded nipple and the crush nut, were going to go ahead and add the barb fitting. The barb fitting will fit directly into the thread and threaded nipple and then well tighten it down. Now, were ready to go ahead and move the top cover. Well just set it aside for installation later. Next, to gain more access to make it easier for our install, were going to go ahead and remove the front grill. Now with our grill off, we need to find a suitable location to mount our new cooler. Because of the size of our new cooler, not just any location will work. So what were going to do, well go ahead and remove the bottom brace, get them behind it, then well be able to take our cooler and attach it directly to the bottom brace. Once we get our cooler back in line to the brace, well go ahead and reinstall the brace. Next, what Ill do is go ahead and pre-drill a couple of small holes to the brace so that we can use self-tappers to go the bracket on the new cooler. Using my yellow marker, we can go ahead and mark the orientation on where I want to drill the hole then Ill just go ahead and move the cooler aside to make sure that we dont drill through the brace into the cooler. For added security, you can also drop in a block of wood behind where youre drilling to make sure you dont puncture the airconditioner condenser. Alright, with the drivers side done, well go ahead and move over to the passengers side. Now, lets go ahead and position our cooler so we can go ahead and install our self-tapping screws to hold it in position. Once you get it in line back up and in position, Im going to go ahead and take a pair of Vise-Grips to hold it in place. Any Vise-Grips or clamp will do. Alright, now that we have our fastener installed, well go ahead and remove our clamp and were ready to start routing our lines. Taking a utility knife, I'm just going to cut off a larger section around this already preexisting opening. This is going to give us ample room to route our hoses. Now, lets go ahead and start installing our lines. Well go ahead and take our hose and our hose clamp. I'm going to gently tighten the hose clamp onto the hose just to secure it while we get it installed. Well route our hose down underneath the. While theyre in, well go into the transmission cooler. Before installing your hose onto the cooler, I recommend to take a little of the new transmission fluid, draw and put it on the hose, and on the nipple of the cooler. It will make it easier to slide your new hose up into position. Now once I get my hose in position, Ill go ahead and loosen the hose clamp back up, move it up into position and then tighten it down. Now with the drivers side down, Ill go ahead and repeat the same process on the passengers side. Well go ahead and get underneath the vehicle, finish routing our hoses to the nipples that we preinstalled earlier. Once your route your hose to the preexisting nipple, well go ahead and cut off any excess hose that wont be needed. And again, before we try and slide it onto the nipple, well take our hose clamp. Well go ahead and clip it up onto the hose. Set it up out of our way for the time being. Put some transmission fluid on the hose and the nipple. I want to lubricate it thoroughly as it will help slide the hose onto the nipple. Once we get the hose onto the nipple. Once we get the hose onto the nipple. Well go ahead and bring our clamp back in and tighten it down. Alright, now weve got that side down, well go ahead and repeat the same process with the other side. Alright, now that weve made our connection, it completes the install portion of our transmission cooler. Lets go ahead and start it up and test for leaks. Now that weve tested for leaks, were ready to go ahead and secure our lines. I'm just going to take a couple of the black zip ties and secure the two lines together at the coupling, and then also where the two hoses meet as they go around the core support. With our zip ties installed, Ill just go ahead and take my side cutter and cut up the excess from the zip ties. Now, were ready to go ahead and reinstall everything. Now that weve completed reassembling the vehicle, lets go ahead and check the fluid level on the transmission. Well pull the transmission dipstick out and see where it seats this time. As you can see, its well below the fuel line. Lets go ahead and add some fluid and then well double check it. Now, were well within the tolerance of the transmission fluid level on the dipstick. This will complete the install of our Derale Performance Transmission Cooler part number D13504 for our 2003 GMC Yukon XL.