I have a 2004.5 with the 48RE, and it’s time for a transmission rebuild. Was running fine, and within a couple miles it started slipping in every gear and making a noise near the converter or front pump. I checked the accumulator pressure with a gauge, and it’s about half the published values in the manual. My question isn’t if I need a rebuild, it’s how much I should spend. I’m in Houston and found a shop that just does trucks - good reviews, and I was comfortable talking through the options with them. Here are my 3 options, sorted by price:

Rebuild myself with triple disc converter, billet input shaft, flex plate, aftermarket valve body, and Goerend rebuild kit.
$2,600

Have the shop do it (they pull, rebuild, and reinstall) with new single disc converter, standard rebuild kit, and valve body mods to raise the pressure.
$2,800

Have the shop do, but add all the parts I’d put in if I did the rebuild.
$5,400

I have the money to pick any of the above, but of course I’d rather spend it on something else. The truck is completely stock except for a Smarty Jr that I leave on tow (SW2, with defaults). I tow 5,000-8,000, but very rarely (maybe 4 times a year). The truck is not my daily driver, but I bought it new and don’t plan to ever sell it. On paper, the stock rebuild should be fine, but I’ve always been worried about the transmission as a weak link. The upgraded parts would make me ‘feel’ better. And I already have more projects than I have time for, so going the cheap route (rebuild myself) means I won’t have a truck for awhile.

What would you do?

 

How many miles on the trucks transmission before you had to do the rebuild?

with as little as you tow, I would just do the shop standard rebuild.

 

It has right at 100k miles.

 

Check into a Suncoast replacement trans. If you plan to keep it, go with an upgrade so you don’t have to deal with it in another 100,000 miles, or less.

 

If I was going to keep the truck forever, I would do the upgrades. The big question would be whether I felt like doing the job myself or not.

 

Have you checked out Firepunk Transmissions? They have an option for a rebuilt tranny specially built for towing (Towmaster Plus).

Their words:

Great For Mildly Modified Trucks Up To 400HP
2-Year Unlimited Mileage, 100% Workmanship Warranty
Build List:

Competition Master Kit (includes added clutches in Direct drum and in OD Brake. OD direct clutch modification and oversized HD 2nd gear band)
Billet Servo
Billet Strut
Billet Anchor
Billet Accumulator Piston
Billet 4.2 Ratio Apply lever
Billet Reman Triple Disc Torque Converter by DPC (1 year warranty)
OEM Input Shaft
Firepunk Towing Valve Body
Deep Pan with drain plug + temp sender port

It doesn't have a billet input shaft. But it sounds pretty strong and I have read good things about them. However, by the time you ship it and labor to install it, you're probably near the cost of your shop-built Goerend.

They're on the short list for when I need one. My 2004.5 is completely stock and has almost 90k on the clock. I tow 12k lbs 4-5 times a year.

 

My take on it would be if you are having to ask the question of wether or not to do it yourself you would be best off to just have it all done by a reputable source of your choosing.

 

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