Trans cooler with front Curt hitch

jfkmk

Original poster
Member
Mar 7, 2013
91
Hello,

New to the site, but it looks like a lot of good information here. I have an 06 Envoy that I just started to tow a 3500# TT with. The Envoy has 50K on the clock, so it is time to change the trans fluid, differential fluid, etc., and after looking at posts regarding towing, I've decided to install a trans cooler. I've also installed a Curt front receiver hitch so I can mount my bike rack when towing the trailer. My questions are these. What cooler is recommended? I don't have a flaring tool, so what adapters, etc. can anyone recommend? Lastly, and the reason I mention the hitch, will the hitch interfere with the installation? It is pretty close to the radiator, so I'm not sure if they would fit.

Thanks in advance for your help!
 

Mark20

Member
Dec 6, 2011
1,630
You should be good with the hitch. eTrailer.com carries coolers and adapter that will let you plug right into the radiator's internal tranny cooler's outlet and then into the external cooler and then back to the return line. No cutting or flaring necessary.
 

tblazerdude

Member
Dec 4, 2011
321
Indeed they do fit in front of the radiator, as I have one located there. If you are facing the truck it is located in the upper left hand corner of the radiator. Passenger side upper radiator. This is one of the few things I did not do to my truck, as I outsourced it to a local transmission shop weeks after purchasing the vehicle in 2007. I believe it is a Hayden ultra cool that measures around 9 by 7. Not sure on the exact model or anything. It cost $100 installed, since I also had them do a transmission fluid exchange. here are some pictures that might help you. A front hitch should not effect the lines in anyway. Remember to use dexVI transmission fluid or better, no dexIII. Here is why;
DEXRON-VI is generally Gp III although the spec does not preclude the use of PAO/Ester base combinations. The confusion arises because in the USA group III stocks can be labelled as synthetic.
Yes DEXRON-VI was designed to be backward compatable so it can be used in all Hydramatic transmisions that called for DEXRON-III or earlier DEXRON specifications. Try not to mix DEXRON-III with DEXRON-VI, only because if you do that you are in fact diluting the DEXRON-VI fluid with a less stable product and therefore throwing away much of the advantage. All you need to remember is that DEXRON-VI is far superior to DEXRON-III and also that DEXRON-III no longer 'exists' in terms of licensing so there's no control over the formulations (if you go out and buy a 'DEXRON-III' fluid in reality you have no idea what you're paying for!). In contrast, GM controls the formulations for DEXRON-VI licensed products ... so you know exactly what you're buying.
from whitewolf on Confused on Dex-VI - Bob Is The Oil Guy.

here is the top view, the top is towards the engine/radiator. In and out lines on the left.

View attachment 26655

Here is a front view.

View attachment 26656


Here are the in/out lines running back to the transmission. This picture is taken from the location of the washer tank / air filter region, inside the engine bay.

View attachment 26657


Here is where the rubber lines run to, to the left of the photo is the fan. The bright white portion on the right is the washer tank.

View attachment 26658
 

Attachments

  • post1.jpg
    post1.jpg
    46.2 KB · Views: 24
  • post2.jpg
    post2.jpg
    41 KB · Views: 26
  • post3.jpg
    post3.jpg
    38.6 KB · Views: 23
  • post4.jpg
    post4.jpg
    38.5 KB · Views: 22

ScarabEpic22

Member
Nov 20, 2011
728
If you dont have and dont want to spend the $20 on a flare kit, buy a PCMofNC trans cooler kit. Has all the lines pre-cut, you can get braided lines or rubber, all the mounts are pre-cut, etc. And it mounts in the brake duct so it doesnt block the radiator at all.

I built my own for my 02 because I was on a budget AND it was back in 2006/7 before PCMofNC had their kit. I have their kit on my SS and love it, took me ~2hrs to install it from start to finish with a few test fits.

http://www.pcmofnc.com/index.php?op...ct&path=229_245_250&product_id=157&Itemid=106
 

jfkmk

Original poster
Member
Mar 7, 2013
91
Thanks, everyone, for your prompt and thorough feedback! I'm definitely going to add a trans cooler before camping season. For the price, it can only help and can't hurt. I'll look for a trans temp gauge, but oudside of adding the cooler and changing the fluid, I don't know what I could do to cool the trans!

I was wondering what the Dex VI was verses the III. From the post, it looks like the VI (among some possible other things) is the VI is synthetic (PAO/Esters). Looks like GM got on the synthetic bandwagon, as all the fluids listed seem to be synthetic. I've been using fully sunthetic fluids since 1993, and never considered going back, so synthetic it is!

I had no idea a flare kit was only about 20, I never looked before. At that price, it is worth it to have another tool.

Once I get it installed, I'll post some pictures of the job.

Thanks again, all!
 

Showtyme

Member
Nov 26, 2012
150
You could also add an oversized tranny pan with cooling fins and a drain plug. Im prob doing this in a couple months when it warms up.
 

jfkmk

Original poster
Member
Mar 7, 2013
91
First of all, thanks to everyone who replied to my original question. Also thanks to everyone in general sharing tips and repair/modification experiences. I've saved quite a bit of money doing my own repairs, and the Haynes manual only goes so far.

Anyway, I started to install my Hayden trans cooler this weekend. Didn't get too far, I was also woring on my camper. When I took all of the parts out that came with the trans cooler, I noticed the hose that comes with the cooler is 11/32, and the extra hose I bought (Hayden 106) that supposedly fits my Envoy is 3/8. The 11/32 is noce and tight on the cooler and the adaprer I bought to go into the radiator, and the 3/8 isn't quite so tight.

What have you all used, 11/32 or 3/8? I'd hate to install it and have leaks, so I'd like to make sure I'm using the right size.

Thanks!
 
Dec 4, 2011
520
jfkmk said:
First of all, thanks to everyone who replied to my original question. Also thanks to everyone in general sharing tips and repair/modification experiences. I've saved quite a bit of money doing my own repairs, and the Haynes manual only goes so far.

Anyway, I started to install my Hayden trans cooler this weekend. Didn't get too far, I was also woring on my camper. When I took all of the parts out that came with the trans cooler, I noticed the hose that comes with the cooler is 11/32, and the extra hose I bought (Hayden 106) that supposedly fits my Envoy is 3/8. The 11/32 is noce and tight on the cooler and the adaprer I bought to go into the radiator, and the 3/8 isn't quite so tight.

What have you all used, 11/32 or 3/8? I'd hate to install it and have leaks, so I'd like to make sure I'm using the right size.

Thanks!

Not sure they make an 11/32" hose, 3/8 and 5/16, so that means you are either 1/32 loose or 1/32 tight, the 3/8 will be easier to get on and flow more volume. Just make sure you tighten the clamp snugly.
 

ScarabEpic22

Member
Nov 20, 2011
728
I honestly have no idea what size hose is on my 02, I did it so many years ago and used whatever hose came with the cooler I bought. Ive had a little leakage in the last few years, I just checked last weekend and saw it was leaking a tad again AND that my factory lines are starting to rust. Going to have to swap those out in the next month or two, dont want a factory line rusting through and taking the trans out.
 

Steveinfl

Member
Dec 6, 2011
62
I just did mine recently and used the factory connection to push on barb fitting. I believe it came from pcm for less, (purchased from our classifieds). I ended up using 5/8 Id tubing.

My cooler came with 11/16 as well.
 

Forum Statistics

Threads
23,307
Posts
637,746
Members
18,509
Latest member
Napalm

Members Online