2006-2010 5/8" Allison transmission cooler hose set #50300




Product Description

(RECOMMENDED FOR APPLICATIONS REQUIRING HIGHER FLOW THAN NORMAL. Examples: heavy towing, chipped ecu, larger turbo, propane injection, or modified transmission.)

This is a fix for the commonly leaking transmission cooler hoses for 2006-2010 Chevy, and GMC trucks equipped with the Allison 1000 transmission behind the 6.6 liter duramax, and 8.1l gas engine. These are made out of 5/8" id Gates hydraulic hose with Gates Megacrimp ends. These hoses will handle the pressure, and temperature that the factory hoses will not. Included is everything to make the conversion possible, except for the tools. I also included detailed instructions, which includes a list of required tools to perform the job properly.

Our 5/8" sets may lower transmission temperature up to 40 degrees, based on input from customers.


  • Manufactured by: Red's Auto Rehab


Overall Rating Star Rating
  • Star Rating
    By: July 23, 2014
    After tiring of the continual leaking of the factory transmission cooler lines on my 07 2500HD GMC Duramax, I spotted these 1/2" hoses online and decided to give them a shot. This has turned out to be an outstanding decision. They perform exceptional in both extreme heat & cold; 6 months and 20,000 kilometres later and the hoses and all fittings are dry as a bone. About 6.000 of those kilometres were heavy towing, to Arizona and back, and no problems. My mechanic who performed the install was so impressed he asked me for the info where I got these high quality hoses from. Well done Red's, these are a top quality solution at an excellent price!
  • Star Rating
    By: Guest November 13, 2013
    This is the best solution to a problem that GM has failed to resolve. After seeing both the 1/2", and 5/8" hose sets, I would definitely go with the 5/8" set. The 5/8" sets use quality Gates hoses and fittings, where the 1/2" set uses a generic hose.
  • Star Rating
    By: Kyle Neely December 07, 2012
    I had bought a 2006 duramax in june of 2009 the short hose from the radiator to the cooler was leaking had the dealership replace them before I took possession of the truck. 3 months later the same line was leaking again (thanks GM). After alot of searching and talking with the best GM diesel mechanic in the area I decided to go with the 5/8s Reds Auto Rehab set. I ordered them on a Wednesday afternoon had them sent USPS and still received them by the following Monday. When they got here and I had inspected them im sure I will have no leaking lines. Heavy, solid, good quality hoses and fittings. After you get the bumper, grill, air box brackets, intercooler down pipe and the rest of the plastic out of the way the install of the lines were very easy. The directions Reds supply with their line sets are very good and very detailed. One thing I can tell you is when you route these lines where the olds ones were its a tight area. When you get them in place make sure they aren't drooping down to where the bolt on the steering stabalizer can cut into them when you turn ur wheels. With 2 people this was about a 2 hour install. For the same price as merchant preformance or all season diesel filler pieces, why not go w new lines all together with heavier lines? Thanks for the great quality product Reds.

Qty Discounts Off Price
Web Analytics