Trans Cooler Installation Help

waxer · September 26, 2007

2002 Suburban, NBS, 5.3, Auto.

I recently purchased a B&M Trans Cooler kit that came with the 3/8" hose barbs.

After looking at my OEM setup, I don't have a secondary trans cooler. It's only utilizing the radiator.

I don't really want to cut my stock trans lines, so I was looking at the fittings that go into the radiator. They look to be 1/2" NPT fittings. Can anyone confirm this?

I was looking to return my B&M cooler back to Summit Racing and order the bigger 11" x 11" B&M SuperCooler with the 1/2" NPT female fitings.

My question is... I am having trouble finding the 1/2" Female NPT fittings to run some hose to the B&M cooler, which I'll use 1/2 Hose barb to 1/2" Male NPT adapters to mate to the cooler. The problem now is I'm not finding anything that will bolt directly to the stock trans lines, which look to be 1/2" NPT Male fittings.

Any help would be apreciated in locating some fittings and/or sharing experiences with adding a trans cooler to a NBS Chevy.

Thanks

September 26, 2007

I had the same problem and I was told I was SOL on the matter. I inevitably(and hesitantly)cut the tranny lines and spliced the new lines in because I needed to haul about 4k worth of household goods about 400 miles. It hasn't leaked much at all, but I'm still uneasy about it. I'm actually thinking of buying new lines to return it to stock.

waxer · September 26, 2007

I had the same problem and I was told I was SOL on the matter. I inevitably(and hesitantly)cut the tranny lines and spliced the new lines in because I needed to haul about 4k worth of household goods about 400 miles. It hasn't leaked much at all, but I'm still uneasy about it. I'm actually thinking of buying new lines to return it to stock.

If I have to cut these I definitely will flare the ends, and cut a chunk out of the line so I can splice in rubber hose should I need to remove the B&M cooler.

I was just worried about voiding my warranty should the transmission fail and the dealer notices that I cut the trans cooler lines. I guess if that happens then I should swap in some new lines before taking it to the dealer

I'm planning on not using the radiator at all for cooling, and just the B&M Cooler. But I've read mixed opinions on that.

Hopefully I can find the right 1/2 Male NPT to hose barb fittings to mate to this B&M cooler.

Anyways, thanks for your reply.

C & A s Dad · September 26, 2007

Waxer,

A couple of things I may be able to help you with. I have a 02 Yuk XL and upgraded my OE aux trans cooler to a larger one because I tow a 6500 lb camper on occasion.

I would strongly recommend you not bypass the radiator. If you do, you will greatly reduce the efficiency of your aux cooler. Let the fluid pass through the radiator and then through the aux cooler and back to your trans. This is the way all mfgs route fluid through an aux cooler.

You should not have to cut your metal lines. The lines should have a rubber section in them just under the right side just behind the radiator. I do not like cutting any of the lines but if you have to cut them, cut the rubber and connect your aux hoses using a good barbed union and if you want you can use 2 clamps on each end for added security. Be careful not to overtighten any of the clamped connections. Tighten the worm drive clamp only until you begin to see rubber protrude throught the slots in the band. If you do this, they will not come off or leak.

I am pretty confident the connections in your radiator are not pipe thread. If they are, you could easily find NPT fittings with barbs. Hyd hose fittings like used on ag and heavy equip use NPT and barbs but again, I am almost positive your fittings are not NPT.

My truck had an OE style aux cooler so I just used the existing lines to connect to my upgrade cooler. However, I am sure you have the rubber sections in your lines.

I have some good digital pics of mine installed. PM me your e mail address and I will send them to you if would like.

The B & M Cooler you bought. It is a stacked plate designed cooler right? Also, is it the 3/4" thick model or the 1 1/2" thick model and what size is it. What part of the country do you live in? I asked all of this because it is possible to use too large of a cooler in colder climates and you could possibly overcool the fluid in the winter. Not an issue for me in Mississippi.

PM me you e mail and I will send the pics and will be glad to help you in any other way if I can. I do not claim to be an expert in any field but I have done a great deal of research on trans coolers and even was able to spend some time with one of the engineers from our supplier, Hayden.

az'03Silverado · September 27, 2007

If you exchange the B&M cooler, get the B&M Supercooler for 26,000lb GVW vehicles. It will come with all of the fitting you'll need to route hose from the radiator cooler to the supercooler. This is what I did with no cutting.

waxer · September 28, 2007

If you exchange the B&M cooler, get the B&M Supercooler for 26,000lb GVW vehicles. It will come with all of the fitting you'll need to route hose from the radiator cooler to the supercooler. This is what I did with no cutting.

Do you have a part number on that? I looked at all of them and the only ones that came with Kits were the smaller ones.

az'03Silverado · September 28, 2007

I couldn't find the part number. Sorry. It's been about 3 years since I installed it and now the categorize them by BTU's and not be the vehicle GVWR. I do know that it's the biggest one they made back then.

topdj · September 28, 2007

I have a summit 2 quart pan IM not using, has the allen head screws and a new gasket,

this was well in the 100 dollar range Id put it on but the dealer saud dont just in case GM wants to blame a trans failure on the pan install. if anyone is interested email me I will send you pics

fits 700 and 4le60

jeff1018 · October 1, 2007

If you have to cut your lines be sure to deburr them and flare them, I learned that the hard way. When you clamp the lines on, Position the clamps in opposite directions, this helps hold the lines better in case you accidently over tighten the one clamp and don't realize it. Also I would recommend not using the lines that come with the kit, my lines blew out twice before I went to Napa and bought their premium transmission lines, the quality was night and day. Periodically check the lines every month or so for damage, especially where the lines is streched over the flare on the metal lines, that portion is prone to cracking with the heat. I'm definatly not an expert, but I learned this advise the hard way. If you question yourself on the dependability of anything during the install, then it's probably not ok. There's nothing worse then pumping out all your transmission fluid!!!

C & A s Dad · October 1, 2007

If you had the rubber trans line blow out you either had some really cheap hose that came with your cooler or you have a pres issue with your pump. The rubber hose supplied with our kits by Hayden are really heavy and I have never heard one issue with the lines bursting. Gates also offers a real quality cooler line. Just be sure you do not use common fuel hose. It will not work for long.

jeff1018 · October 2, 2007

I used whatever lines came with the B&M kit, not really sure what kind they were, but they were definatly junk.

peterparley · January 14, 2008

I know this is an old thread, but it's one that I ran across when trying to figure out how to attach a Hayden trans-cooler to my 2007 NBS Sierra. Thought posting here might help anyone else who runs across this topic.

Basically, I didn't want to cut the hose, so I e-mailed Hayden. They said that I needed part #397 (not listed in the instructions), which fits into the quick connect fitting in the transmission. Bruce Stone at Hayden gave me several part numbers to look for at different stores. NAPA (part no: 1-8440), Pep Boys (397), Advance (2400397), Kragen, Checker, Chucks (397), and Carquest (77634). Carquest got one for me the next day.

This past weekend I installed the trans-cooler. Followed the instructions, clamping everything together and securing the trans-cooler. I then disconnected the transmission hose from the quick disconnect fitting (the upper hose is the return line). I used a Jiffy-tite quick disconnect tool, but a screwdriver or ice pick would also work to remove the retaining clip. Plugged in part #397, clamped the return line from the trans-cooler to the return line to the transmission, and was good to go.