Sierra Transmission Oil Cooler 18-2588 for Chrysler Inboard Engines, 1 1/4 Inch Water Inlet

The Sierra 18-2588 Transmission Oil Cooler is a bare metal marine transmission oil cooler built for Chrysler Inboard applications. It uses a 1 1/4 inch water hose connection and a 10 inch tube bundle with an overall length of 12 inches, giving it the cooling surface needed to keep transmission oil temperature under control during sustained inboard operation.

Oil enters and exits through a 9 inch x 2 inch fitting with a 3/8 inch NPT inlet/outlet, and the unit is rated for up to 6 GPM of oil flow and up to 25 GPM of water flow. It ships bare metal, ready for primer and factory paint finish, so it can be finished to match the engine compartment or left as-is for service use. The stainless steel construction is built to hold up in the marine environment where the cooler is mounted in the raw water cooling circuit.

This oil cooler is designed as a direct-fit replacement for the transmission cooling system on Chrysler Inboard engines, giving boat owners a straightforward way to restore proper transmission oil temperature control without modifying existing hose and fitting connections.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-2588
• Application: Chrysler Inboard Transmission Cooler
• Water Hose Connection: 1 1/4 inch
• Oil Fitting: 9 inch x 2 inch, 3/8 inch NPT inlet/outlet
• Oil Flow Rate: 6 GPM maximum
• Water Flow Rate: 25 GPM maximum
• Tube Bundle Length: 10 inches
• Overall Length: 12 inches
• Water Inlet and Outlet: 1 1/4 inch
• Finish: Bare metal, ready for primer and factory paint finish
• Material: Stainless steel
• Weight: 2.83 pounds

Fitment

Chrysler Inboard engines using a transmission oil cooler with a 1 1/4 inch water hose connection.

Frequently Asked Questions

What does the Sierra 18-2588 transmission oil cooler fit? The Sierra 18-2588 is built as a transmission oil cooler for Chrysler Inboard engines, using a 1 1/4 inch water hose connection to tie into the existing raw water cooling circuit.

What size is the water hose connection? The 18-2588 uses a 1 1/4 inch water hose connection on both the inlet and outlet.

How large is the cooler's tube bundle? The tube bundle measures 10 inches, with an overall unit length of 12 inches.

What size are the oil fittings? Oil fittings on the 18-2588 measure 9 inch x 2 inch with a 3/8 inch NPT inlet and outlet connection.

What is the maximum oil and water flow rating? The Sierra 18-2588 is rated for up to 6 GPM of oil flow and up to 25 GPM of water flow.

Does the 18-2588 come painted? No, it ships bare metal and is ready for primer and factory paint finish, so it can be painted to match the engine before or after installation.

What material is the cooler made from? The Sierra 18-2588 transmission oil cooler is constructed from stainless steel.

How much does the 18-2588 weigh? This transmission oil cooler weighs 2.83 pounds.

Is the Sierra 18-2588 a direct replacement for the factory Chrysler Inboard transmission cooler? Yes, the 18-2588 is designed to replace the Chrysler Inboard transmission oil cooler using the same 1 1/4 inch water hose connection and NPT oil fitting sizing.

What is included when I order part number 18-2588? Ordering 18-2588 gets you the complete transmission oil cooler unit, ready for installation once primed and painted as needed.

Can this cooler be installed without additional plumbing modifications? Because the 18-2588 uses the standard 1 1/4 inch water connection and 3/8 inch NPT oil fitting, it is intended to connect using the same hose and fitting sizes as the original Chrysler Inboard transmission cooler.