2004 Yukon XL transmission slipping - should I replace both engine and trans?

[rhondabh3]

Just joined and im really thankful to find this forum.

My transmission is slipping and I’ve got decisions yo make about repairs so I have some questions and hope you guys can help. I bought this vehicle in 2008 from a friend who bought it new. At the time it had 115,00 miles. I now have 258,000 on my Yukon. I LOVE this vehicle!! It serves all my needs! I’ve kept it maintained and I think I’m pretty blessed that it’s gone this far without major engine or transmission problems. I did just dodge $900 on repairing AC.

My question now is, if I need a transmission should I go ahead and replace engine at the same time considering tge miles on it and it’s started using oil and pressure isn’t as good as it once was.

Next question is where should I get trans and engine and what kind??? I need to know I’m dealing with trustworthy company. I have local repair shop who will do the swap.

Im 66 yo female and I obviously cannot do that. Although I did used to own a 79 z28 and I could replace plugs n valve cover gaskets etc. so I know enough about mechanics to be dangerous. Lol.

 

[Sam Harris]

Welcome to the forum, from Colorado!

First, I’m glad you’re enjoying your Yukon, I love mine as well!
I wouldn’t plan to replace the engine, unless there’s a real need to do so. However, if you want to do some upgrades, and it’s in the budget, I think we’re all about doing things to improve these rides..

Replacing the transmission will require some decisions to be made.. if you’re planning on adding a good amount of power, you might look into a 4L80 conversion, but will need someone familiar with making the necessary modifications for that. (Cutting / welding the trans crissmember, and also some wiring changes) The biggest drawback to the conversion in my opinion, is the work, and also the different gearing in the 4L80. First gear makes it a bit harder to get off the line, but again, depends on your power goals.. I’m planning to get a well-built 4L60 for mine when the time comes, and likely from Performabuilt, as I’ve heard good things about their transmissions, and especially their customer service.

 

[Bill 1960]

Welcome! If it were me, I’d ask myself if I liked the vehicle enough to spend more on maintenance than it’s worth.

There’s a lengthy thread running right now by someone who paid for a transmission rebuild that ended badly. My opinion is a cheaper transmission repair and a lot of the remanufactured stuff sold is a crapshoot. I bought a GM reman myself which is 3-4 grand installed but I can depend on it and it’s backed up by GM.

An engine replacement will be another big bill $$$$.

Yes, you can certainly do those repairs and keep the vehicle going indefinitely as long as it’s not rusted.

Or, you could sell or trade it on a newer vehicle and add the ten grand you’re likely to spend on this in the next couple of years.

The best, low cost way to operate a vehicle is buy it used to avoid depreciation, then get rid of it when the major items are worn out but still operating.

 

[Rocket Man]

If you just want to keep it stock like I assume you do, I’d put a GM remanufactured trans in it from a dealer for the warranty and run it until it dies. You probably have another 150-200,000 miles left on the engine as long as you keep it maintained. The 00-06 trucks seem to last forever, or at least 400-500,000 miles.

 

[Teamiez]

My trans went at 122K and the reman I got is still going strong for kind of getting beat on. Flipping 198,000. Happy to have a very reliable transmission shop in a near by town. The local schools take there auto mechanic students there for tours and what not. I was told my 4L60E is more like a 4L65E with what they do.

 

[rockola1971]

No need for engine replacement now. Maybe oil pump though. Id have the tranny rebuilt. Find a reputable tranny shop that has a warranty (most do). Get estimates from atleast 2 reputable shops. Dont be afraid to try a shop from a nearby town or a very large city nearby.

Is it 2nd and 4th (overdrive) Slipping or 1st gear or all gears?