The SPOOLOGIC Turbo Coolant Line (Lower Return) SL-360-032 is a direct-replacement turbo coolant line (lower return) for 2013-2018 6.7L Cummins applications. Built to OE form and fit, it carries coolant back from the turbo center section to the cooling system and terminates in one banjo fitting and one threaded adapter fitting — sealed by two crush washers on the banjo end and two O-rings on the adapter, with one banjo bolt to torque the banjo end down. Backed by a 1-Year Limited Warranty.

Why You Replace the Coolant Line — Not Just the Bolts

Coolant lines and their seals are not designed to be reused forever. Here’s what’s actually happening to the parts you’re tempted to put back:

• OE coolant lines corrode and crack from the inside out. The tubing runs coolant through the hottest zone of the engine bay, cycling from cold soak to 200°F+ operating temp thousands of times. Internal scale and external road salt eat the line until pinhole leaks show up at the crimps or the bends.
• Braided flex sections harden and split. The flexible section absorbs engine movement and thermal expansion. Eventually the inner liner goes brittle and cracks — coolant sprays onto a hot turbo and the truck overheats fast.
• Crush washers are single-use. The washers deform to seal the banjo joint. Reused washers won’t re-form to the mating face and will weep coolant at every heat cycle.
• Adapter O-rings are single-use too. The O-rings on the threaded adapter take a permanent compression set the moment they’re torqued down. Reused O-rings leak at the block port.

Component Breakdown — What Each Piece Does

• 1 coolant line — rigid steel tubing joined by a braided flexible center section, formed to OE geometry so it clears the surrounding components and drops into the factory routing.
• 1 banjo bolt — hollow, cross-drilled bolt that passes coolant through the banjo eye at one end of the line.
• 2 banjo crush washers — one on each side of the banjo eye. Seal the coolant passage against the mating surface when the bolt is torqued down.
• 1 threaded adapter fitting with 2 O-rings — screws into the block-side port and mates with the threaded end of the coolant line. The two included O-rings seal the adapter’s block-side and line-side threads.

Material Technology — Why Each Material Was Chosen

• Rigid steel tubing with braided flex center — the line body is formed steel with a braided coolant-rated hose section in the middle to absorb engine movement and thermal expansion.
• Steel banjo bolt — correct grade, length, and thread pitch for the turbo-side coolant port.
• Single-use crush washers — deform when torqued to form a fluid-tight seal between the banjo eye and the port face. Not reusable — every install gets a fresh set.
• Machined steel threaded adapter — correct thread pitch and seat geometry to torque into the block coolant port and mate with the coolant line.
• Elastomer O-rings — correct material and durometer for engine-coolant temperatures, sized for the adapter grooves so they seat without rolling or extruding.

Install Notes

• Drain the cooling system before removing the old line — open the radiator drain and catch the coolant in a clean pan for reuse or disposal.
• Clean the block and turbo coolant port mating surfaces with a plastic scraper and a lint-free rag before setting the new line. Old crush washer residue, coolant crust, or scale on the ports will keep the new washers from sealing.
• Install fresh crush washers on the banjo end every time — one on each side of the banjo eye. Reused crush washers weep coolant.
• Thread the adapter fitting into the block by hand first — do not use an impact. Inspect both O-rings before install; make sure they’re seated in their grooves and not pinched.
• Torque the banjo bolt to Cummins service manual spec. Over-torque crushes the washers past their seal range; under-torque leaks.
• Route the line through the factory brackets and clips — the tubing was bent to clear specific components. Skipping the brackets lets the line rub through under vibration.
• Refill with the correct Mopar OAT specification coolant, bleed the system per the service manual, and inspect every joint after a full heat cycle.

What’s Included

• 1 turbo coolant line (rigid steel + braided flex center)
• 1 banjo bolt
• 2 banjo crush washers
• 1 threaded adapter fitting with 2 O-rings

Interchange / Cross-Reference

• Mopar OEM 68210187AA — turbo coolant line (lower return)

Features

• Direct-replacement turbo coolant line (lower return) for 2013-2018 6.7L Cummins applications
• Rigid steel + braided flex line with one banjo end and one threaded adapter end
• Ships with 1 banjo bolt, 2 crush washers, and 1 threaded adapter fitting with 2 O-rings
• OE form and fit — direct replacement, no modifications
• Backed by a 1-Year Limited Warranty

Fits 2013-2018 6.7L Cummins

• 2013 – 2018 Ram 2500 3500 4500 5500 6.7L Cummins

1-Year Limited Warranty

Every SPOOLOGIC turbo coolant line is covered by a 1-Year Limited Warranty against defects in materials and workmanship from the date of purchase. Warranty covers replacement of the part only. Warranty does not cover labor, towing, downtime, consequential damages, failures caused by improper installation, failures caused by dirty or damaged mating surfaces, reuse of any included O-ring or crush washer, or use outside the listed fitment.