Description
New Connecting Rod for Detroit Diesel DD15 Engines, Part Number A4720300320
Why Choose This Detroit Diesel DD15 Connecting Rod From HHP?
- Brand new construction built to OEM specifications for proper fitment and function
- Manufactured in an ISO 9001:2015 certified facility for quality and consistency
- Crafted with hard-wearing strength and durability to handle the demands of heavy duty operation
- No core charge required
- Backed by a 90 Day Parts Warranty from HHP
- Cross references A4720300020, A4720300120, A4720300220, A4720300520, EA4720300320, EA4720300520, HBRA4720300520, 671662, 671662-006, and 671662006
Why a Worn or Damaged Connecting Rod Is a Problem You Cannot Ignore
The connecting rod is one of the most mechanically stressed components inside any diesel engine, and the DD15 is no exception. Its job is to transfer the force of combustion from the piston down to the crankshaft, converting linear motion into the rotational power that moves the truck. Every power stroke puts enormous load on the rod, its bearings, and its fasteners. Over hundreds of thousands of miles, that load adds up.
When a connecting rod begins to fail on a Detroit Diesel DD15, the warning signs are hard to miss. A deep, rhythmic knock from inside the engine block is one of the most telling indicators of a rod bearing or rod body that has lost its clearance or structural integrity. Excessive oil consumption, low oil pressure at idle, and metal particles in the oil are all signs that internal components are breaking down. Left unaddressed, a failing connecting rod can cause catastrophic engine damage including a spun bearing, a bent rod, or in the worst case a rod that breaks through the engine block entirely. Catching and replacing a damaged rod early is far less costly than addressing the damage a failed rod leaves behind.
About This Detroit Diesel DD15 Connecting Rod
This is a brand new connecting rod, HHP part number A4720300320, engineered as a direct fit replacement for Detroit Diesel DD15 diesel engines. It cross references a broad list of OEM and aftermarket numbers including A4720300020, A4720300120, A4720300220, A4720300520, EA4720300320, EA4720300520, HBRA4720300520, 671662, 671662-006, and 671662006. If your existing rod or rod assembly carries any of these numbers, this unit is the correct replacement.
This connecting rod weighs 12 lbs and ships in a 21 by 9 by 8 inch package. There is no core charge on this part, so no deposit is required and nothing needs to be returned after installation. Because diesel engine components are engine specific, entering your Engine Serial Number or VIN on the product page before ordering allows HHP’s team to verify fitment for your specific DD15 build before the part ships, helping you avoid the cost and delay of an incorrect order.
Get Your Detroit Diesel DD15 Connecting Rod From Highway and Heavy Parts
At $310.73 per rod with no core charge, same-day shipping on in-stock orders placed by 2PM EST, and a 90 Day Parts Warranty, this is a reliable, cost-effective replacement for any DD15 rebuild or bottom-end repair. HHP’s ASE certified technicians are on staff to help you confirm fitment, diagnose the cause of engine knock, or answer any installation questions before and after your purchase. Financing is also available through PayPal Pay Later and Sezzle for qualified buyers.
Order your Detroit Diesel DD15 Connecting Rod (A4720300320) from HHP today.
FAQs About Detroit Diesel DD15 Connecting Rod (A4720300320)
1. What engines does connecting rod A4720300320 fit?
This connecting rod is built for Detroit Diesel DD15 diesel engines. HHP recommends submitting your Engine Serial Number or VIN before ordering so our team can confirm this is the correct rod for your specific DD15 application.
2. What OEM part numbers does A4720300320 replace?
This rod cross references A4720300020, A4720300120, A4720300220, A4720300520, EA4720300320, EA4720300520, HBRA4720300520, 671662, 671662-006, and 671662006. If your existing rod carries any of these numbers, this is the correct replacement.
3. Is this connecting rod new or remanufactured?
This is a brand new connecting rod manufactured in an ISO 9001:2015 certified facility to OEM specifications for proper fitment and function. It is not remanufactured or reconditioned.
4. What are the symptoms of a failing connecting rod on a Detroit Diesel DD15?
The most common symptom is a deep, rhythmic knocking sound from inside the engine block that changes with RPM. Other indicators include excessive oil consumption, low oil pressure at idle, metal particles or shavings found in the oil during an oil change, and in severe cases visible damage to the engine block itself. Any of these symptoms warrants immediate inspection of the bottom end.
5. What causes connecting rod failure on the DD15?
The most common causes are oil starvation due to low oil pressure or a failed oil pump, bearing wear from extended oil change intervals, detonation or combustion irregularities that overload the rod, and fatigue failure in high-mileage engines that have never had the bottom end refreshed. Diagnosing and correcting the root cause before installing a new rod is essential to prevent repeat failure.
6. Is there a core charge on this connecting rod?
No. This connecting rod carries zero core charge. There is no deposit required at checkout and nothing to return after the repair is complete.
7. What warranty comes with this connecting rod?
HHP backs this Detroit Diesel DD15 connecting rod with a 90 Day Parts Warranty covering quality and fitment from the date of purchase.
8. How fast will this connecting rod ship?
In-stock orders placed by 2PM EST ship the same day, Monday through Friday. The rod weighs 12 lbs and ships in a 21 by 9 by 8 inch package via UPS or FedEx, with delivery timelines depending on your location.
9. Should I replace all connecting rods at once or just the damaged one?
If the engine is already torn down for a bottom-end repair and other rods show wear at the bearings or show any scoring, replacing all rods or at minimum all rod bearings at the same time is the more cost-effective approach. Doing so eliminates the risk of a second teardown shortly after the first. HHP’s ASE certified technicians can help you evaluate your situation and determine the right scope of repair.
10. Can HHP help me confirm this is the right connecting rod for my DD15 before I order?
Yes. HHP has ASE certified technicians on staff who can cross reference your Engine Serial Number, VIN, and existing part numbers to confirm that A4720300320 is the correct connecting rod for your Detroit Diesel DD15 before your order is placed.
