TSD.performance

04/22/2026

S400 Duramax L5P came in burning coolant and smoking white — traced back to a cracked cylinder head.

Repaired with a new cylinder head and ARP 625 head studs to ensure long-term reliability under pressure.

P&C Coating handled the powder coating, giving the engine bay a clean, finished look.

Upgraded with a DP Customs CCV reroute kit, AN heater core hoses, and UDT 4K+ RPM tuning!

Clean, dialed, and back on the road.

📞 563-542-2980
📧 [email protected]
Top Secret Diesel Performance & Repair

01/30/2026

🔥 BOOST SEASON 🔥
6.7 Powerstroke in the shop getting a KC Turbos Stage 1 upgrade 💨

Quicker spool. Harder pull. Better drivability.
One of the best all-around upgrades for a street-driven 6.7 that still wants to rip.

No shortcuts. No guesswork.
Diesel done right.

📍 Top Secret Diesel Performance
📞 563-542-2980
📧 [email protected]

01/27/2026

🔥 TURNED UP & HEADED OUT 🔥
L5P rolling out after a Dan’s Diesel Stage 2 64mm turbo and WC Fab cold air intake

Built to pull hard and run strong every time it hits the throttle.

No shortcuts. No compromises.
Diesel done right.

📍 Top Secret Diesel Performance
📞 563-542-2980
📧 [email protected]

12/25/2025

11/07/2025

Stock turbo just got replaced with a Fleece Cheetah drop in turbo!
Better response, more airflow, and a serious bump in performance!

Whether you’re after towing power or track-ready performance, we’ve got the setup for you.

👉 Message us to book your appointment today!

📲 563-542-2980
📧 [email protected]
🌐 topsecretdieselperformance.com

09/09/2025

2019 6.7 Power Stroke headed home after some upgrades!

✅ SPE oil pan & oil filter housing
✅ PPE deep transmission pan
✅ SPE upper & lower radiator hoses
✅ PPE intercooler

Cooling, durability, and serviceability all taken to the next level. This truck is ready for anything! 🔥

📞 Call us today to get your setup dialed in!

📲 563-542-2980
📧 [email protected]
🌐 topsecretdieselperformance.com

09/03/2025

🚨 6.7L Cummins in the shop for the BD Grid Heater upgrade! 🚨

Don’t wait until the factory unit fails and causes serious engine damage. The BD upgrade is a proven fix that keeps your truck safe and reliable.

📞 Get ahold of us today to schedule your install and protect your investment!

📲 563-542-2980
📧 [email protected]
🌐 topsecretdieselperformance.com

08/25/2025

🚨 NOW HIRING – Light Duty Diesel Mechanic 🚨
We’re looking for 2 experienced diesel techs to join the team!

🛠️ From routine maintenance to full-blown performance builds – if you know your way around a Cummins, Duramax, or Power Stroke, we want to talk to you.

💵 Pay based on experience
🕒 Full-time preferred
🔧 Must have pervious mechanic experience
🔥 Paid Time Off
👉Retirement Plan

We work on everything from daily drivers to high-horsepower builds. If you’re passionate, reliable, and take pride in your work — come be a part of a shop that gets it done right.

📞 Message us here or call/text 563-542-2980
📧 Or send a resume to [email protected]

Tag someone who needs to see this!nt

07/15/2025

🚨 NOW HIRING – Light Duty Diesel Mechanic 🚨
We’re looking for an experienced diesel tech to join the team!

🛠️ From routine maintenance to full-blown performance builds – if you know your way around a Cummins, Duramax, or Power Stroke, we want to talk to you.

💵 Pay based on experience
🕒 Full-time preferred
🔧 Must have pervious mechanic experience

We work on everything from daily drivers to high-horsepower builds. If you’re passionate, reliable, and take pride in your work — come be a part of a shop that gets it done right.

📞 Message us here or call/text 563-542-2980
📧 Or send a resume to [email protected]

Tag someone who needs to see this!

06/25/2025

Our website is now live! Go check it out and order some parts for your ride!

Top Secret Diesel Performance and Repair