What This Hose Actually Does
This is the hump section between the CAC pipe and the intake side on the WorkStar 7700 - it's not a straight coupler, it's molded with that offset bend to soak up engine movement and vibration without stressing the metal pipes on either end. When it goes, you'll see boost leaks, black smoke under load, or just a hose that looks like a dried-out inner tube with cracks running the circumference.
Silicone construction on this one is standard - the factory rubber didn't hold up great to underhood heat cycling on these trucks, so most of what you find in the aftermarket now is silicone with the wire reinforcement built in. That's not an upgrade claim, that's just what's available and it tends to outlast the OE material.
Bore is 4 inch, and the hump shape and hose length are specific to where this sits on the 7700 - it's not a piece you can trim out of a straight coupler and make work.
Why All These Numbers Cross
1673866C1 and 2014134C1/C2 are International's own part numbers, and they show up together because International revised the number over the years without changing the physical part - same hose, same application, just a running change in their system. Automann's 07-07010002 and the 3541592C1/3543541C1/266389C91 numbers are the aftermarket and International parts-counter equivalents that reference back to the same hump hose.
Where this can get you in trouble is confusing hump hoses across different truck models or different CAC routing - Kenworth and Peterbilt used similar-diameter silicone hump sections on some builds, and while the interchange list shows crossover, the bend angle and leg lengths aren't universal across every chassis. Detroit's A4600981707 is listed because some of these WorkStars ran Detroit engines with compatible CAC plumbing, not because it's a blanket fit for every Detroit-powered truck.
Bottom line: match by the number stamped or molded on your old hose, not by truck brand alone. If the number's worn off, pull your VIN and we'll run it or measure bore, overall length, and leg dimensions off the old part before you order.
Ordering From PartStop
We keep 1673866C1 and the crossed numbers in stock in Tacoma - if you're local, same-day pickup is normal, and we ship nationwide if you're not close enough to walk in. Comes with our 6+ month warranty, standard on the hoses and clamps we sell.
This is a $45.99 part and a five-minute swap for anyone with basic hand tools and a way to get at the CAC piping. Don't guess on it - confirm the number off the old hose or give us a VIN, and we'll make sure what goes out the door is a direct replacement, not a maybe.
1673866C1 Cross-Reference & Interchange Numbers
These manufacturer and aftermarket numbers commonly cross-reference to 1673866C1. Use them to identify the part — then confirm the exact fit by VIN or the number stamped on your old unit before you order. An interchange is a starting point, not a fitment guarantee.
| Brand / Line | Cross-Reference Numbers |
|---|---|
| Automann (07-07010002) | 2014134C1, 07-07010002, 3541592C1, 3543541C1, 266389C91 |
| Detroit Diesel (OEM) | A4600981707 |
Frequently asked questions
Does 1673866C1 fit my 2018 International WorkStar 7700?
Likely yes for that model year range, but confirm by checking the number cast or molded on your old hose, or give us the VIN - International made a running change from 1673866C1 to 2014134C1/C2 over the years and we want to make sure you get the right one, not just close.
Is this the same as the Automann 07-07010002?
They cross-reference to the same application and dimensions, yes. Automann's part is aftermarket, built to the same hump shape and 4-inch bore as the International numbers - it's a direct replacement, just packaged under their part number instead of International's.
My old hose has no readable number on it - how do I know I'm ordering the right one?
Measure the bore (should be 4 inch), overall length, and the length of each leg off the hump bend, then compare to what we've got listed. Or just bring the old hose to the counter if you're in Tacoma - fastest way to get it right the first time.
Not sure it fits? We check before you pay.
Run your VIN and we’ll match parts to your exact truck, or call the counter — a person who knows trucks verifies fitment by OEM number before the order ships. No wrong-box returns.
More cross-reference guides
Need the part, not just the reading?
Every part below is a Premium Quality aftermarket Direct Replacement with published OEM cross-reference numbers, a 6+ month warranty and same-business-day shipping from Tacoma, WA. Not sure it fits? Run your VIN — or call and a person who knows trucks will verify fitment before you pay.