What This Hose Actually Is
This is a straight silicone coupler with a slight hump in the middle - that hump plus the 3 stainless reinforcement rings is what keeps it from getting sucked flat when the turbo's making boost. 4" ID, 8" length, made to bridge the gap on CAC piping where a rigid pipe would crack from vibration.
Freightliner used this shape and size on a bunch of Cascadia and Columbia configurations, and International carried a nearly identical piece on ProStar and similar models. Different badge, same hose in most cases, because the charge air plumbing dimensions matched up.
Silicone instead of rubber means it handles the heat cycling off the CAC better and won't harden and crack in a couple years like a cheap rubber coupler will.
Why These Numbers Cross
Freightliner F01613S352 and International 1673866C2, 1673866C1, and 3582899C2 all land on this same 4x8 hump hose because both truck makers spec'd their CAC boots from common hose suppliers - when the ID, length, and rib/hump profile match, the part interchanges regardless of what letters are stamped on the box.
Where guys get burned is assuming every 4" hump hose is the same. Check the length first - 8" is a specific spec here, not a 6" or 10" version - and count the reinforcement rings. If your old hose has 2 rings or a different bead pattern near the ends, it's not this same casting even if the ID matches.
Surest way to confirm: pull the old hose and read whatever number is molded or printed on it, or check your VIN against the parts book. Don't just eyeball the ID with a tape measure and call it good - hump hoses look similar but the wall thickness and clamp bead placement vary enough to cause a boost leak if you guess wrong.
Ordering From PartStop
We're in Tacoma and keep this one in stock for same-day pickup or will/call. Order online and we ship it out the same day if you're not local - doesn't matter if you're running out of Spokane or Boise, it gets there.
Comes with our standard 6+ month warranty. If it's the wrong hose for your application we'll swap it, no hassle, just don't wait until it's cracked and leaking boost to check the fitment.
Call the counter if you're not sure which number you need - read us what's on the old hose or give us your VIN and we'll match it up before you order, saves everybody a return shipment.
0121200001 Cross-Reference & Interchange Numbers
These manufacturer and aftermarket numbers commonly cross-reference to 0121200001. 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 |
|---|---|
| Freightliner | F01613S352 |
| International | 1673866C2, 1673866C1, 3582899C2 |
| Aftermarket | FRE1008 0001 |
Frequently asked questions
Does F01613S352 fit my International ProStar?
Likely yes if your CAC boot is the 4" ID, 8" length hump hose with 3 stainless rings - International used it under 1673866C2 and related numbers. Pull your old hose and check the length and ring count, or give us the VIN and we'll confirm before you order.
Is this the same hose as International 1673866C2?
Same physical hose in almost every case - same silicone hump design, same 4x8 dimensions, same 3-ring reinforcement. Freightliner and International sourced this coupler from common suppliers, which is why the numbers cross. Still worth checking your old part number against ours before installing.
How do I know if I need 3 rings versus a smooth hump hose?
Count the rings on your old hose before you order - the ribbed/ring reinforcement handles boost pressure without collapsing under vacuum. If your application specs a smooth hump with no rings, this isn't the right part number even though the ID and length might match.
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.