I read about this problem on this website, but I wanted to create a thread to bring more attn to this. Apparently if you are going to use a 99 4l80e, you have to use rear cooler line fitting which has a longer snout. If you don't the trans is said to fail. I think this is what the problem was with my trans that only lasted about 500ish miles, half of which performance seriously decreased. I am going to install the 80e rear fitting and see if that remedies the problem. If not, I will obviously have to replace/rebuild the trans. I'm not sure if 99 and newer units are correct as i heard of someone with a 98 who had a longer snout in the rear. Here is a link to a thread where this issue is discussed. Vince, seemed to stress the importance on this fitting to.

https://www.performancetrucks.net/fo...s-help-485402/

 

Hmm, myself as well as several others have ran 80e without the long fitting. I have since reverted back, but probably put estimated 15k like that.

But maybe it caused your problems.

 

I also talked to vince on the phone about this little fitting. I put well over 50k miles on mine with just a -6 to 1/4"npt adapter front and rear.
Maybe thats why it whines in 1st and reverse so much. Or when i put it in park.
But its held its fair share of power and still towing alot with it.

When i put the built 80e in it i was sure to use the right fitting. Sold that trans and put my stocker back in along with the factory fittings front and rear.

Maybe the HD2 shift kit and boost valve did something to help it out? I dunno. But id surely use the stock fitting from now own.

 

I would strongly suggest that you repair the tranny. I had this happen, and posted the pic of the different nipple. That nipple off of the fitting goes into the center support, and sends lubrication and coolant to the rear of the tranny. It will take out a planet gear shim in no time. Note the shim in the first pic, and gone in the 2nd. I found part of it in the 3rd pic. Most of that material is from the bushing between the planets. It also beats the snot out of the bushing between the planets #238. If you just run it that way, all of that debris is floating around in your tranny. It will go through your cooler, lines, clutches, and converter. It is basically like sand going through your tranny. When I bought this tranny it did not have the fitting, and I never knew the difference since this was my first tranny rebuild. I ended up getting a core tranny to compare parts to find out the problem, and thats when I found the fitting to be different.

 

Sonnax makes a retro fit kit that i am gonna use on my 80 swap since i allready have -6 an lines and fittings. This way i dont have to extend the lines and it uses the correct rear fitting

 

Thats really cool, I didnt know about that part.

 

Thanks for posting that! I was just about to go looking for a photo of it to show guys what I install on the 80e's I build for my clients. All of them get that part. I try to give my clients more than they bargained for and in the case of the 80e that is it. I have found that when I do conversions that when this adapter is added it just makes the install go so much easier.

And yes, the long snouted fitting is an absolute must on the rear lube units, it cannot be overlooked as the unit will not lube the output aseembly without it.

If you guys need to order that part I can have it drop shipped from my supplier. Just give me a shout and I'll make it happen for ya!

g

 

Keep in mind that all 97 and later units use the long nippled fitting in the rear cooler passage. Just figured I would chime in here and add this.

 

You must rebuild!! My tranny builder did not put in fitting and I lost 3rd gear. He just replaced these parts and did not completely rebuild. Truck broke down with bearing out 1k miles later, see above post about road ripper tranny question.

 

So I just did my 80 e swap and I used my stock 02 cooler lines. The 80e is a 03-04 model. Do I need this longer fitting?