2021 Ram 1500 Classic Regular Cab Bolt Pattern
Checking fitment for your vehicle? Below you will find the factory bolt pattern (also known as the lug pattern) for the 2021 Ram 1500 Classic Regular Cab, along with offset and center bore data.
| Bolt Pattern (Lug Pattern) | 6x139.7 (6x5.5") |
|---|---|
| Lug Nut / Bolt Size | 14x1.5 |
| Center Bore (CB) | 77.8 mm |
| Offset (ET) | 19 |
| Torque Specs | 100 ft-lbs (135 Nm) |
Imperial Match: 6x139.7 is commonly referred to as 6x5.5" in US Standard.
2021 1500 Classic Regular Cab — Year-Specific Fitment Context
The 2021 Ram 1500 Classic Regular Cab is in year 3 of 5 using the 6x139.7 pattern (2019–2023). Wheels from any 2019–2023 Ram 1500 Classic Regular Cab are cross-compatible with the 2021 model.
Ram 1500 Classic Regular Cab Bolt Pattern by Year
The table below shows how the 1500 Classic Regular Cab's wheel specifications have changed over the years. The 2021 model year is highlighted.
6x139.7 Pattern Context
This bolt pattern appears on 1067 vehicles in our current database and is considered common.
Examples of other vehicles using 6x139.7:
Expert Buying Guide for 2021 Ram 1500 Classic Regular Cab
For your 2021 Ram 1500 Classic Regular Cab, the 6x139.7 bolt pattern and 77.8mm center bore are critical. Aftermarket wheels often have a larger center bore (e.g., 78.1mm or 87.1mm), requiring hub-centric rings to prevent vibration and ensure proper load transfer. The offset is sensitive: stock is 19mm, but aftermarket offsets from 0 to +25mm may fit; extreme offsets can cause rubbing or bearing stress. Always use the correct 14x1.5 lug nuts with the proper seat (cone or ball) to avoid wheel loosening. Verify thread engagement and torque to spec.
Historical Fitment Data Reference
In our dataset, Ram 1500 Classic Regular Cab appears from 2019 to 2023 (4 model years). Across recorded model years, this model generally keeps the same bolt pattern.
- Observed bolt-pattern variants for this model: 1
- Observed center-bore variants for this model: 1
- Observed lug-size variants for this model: 1
- Observed total offset span across years: 0.0 mm
Quick Tips & Safety Warnings
- ✅ Re-torque lug nuts after 50-100 miles of driving to account for settling.
- ✅ Avoid using universal fit wheels without hub-centric rings; they can cause vibration and damage.
- ✅ Check for brake caliper clearance when changing offset, especially with larger wheels.
- ⚠️ Torque lugs in a star pattern to 100 ft-lbs (135 Nm), then re-check torque after 50-100 km (30-60 miles).
Ready to upgrade or perform maintenance?
🛒 Shop Tools & Accessories on AmazonAs an Amazon Associate, I earn from qualifying purchases.
2021 Ram 1500 Classic Regular Cab — Frequently Asked Questions
What is the bolt pattern for a 2021 Ram 1500 Classic Regular Cab?
The 2021 Ram 1500 Classic Regular Cab uses a 6x139.7 bolt pattern (also called lug pattern or PCD). The center bore is 77.8mm and the offset is 19mm.
What other years of Ram 1500 Classic Regular Cab have the same bolt pattern as the 2021?
The Ram 1500 Classic Regular Cab uses the 6x139.7 pattern from 2019 through 2023. Wheels from any of these model years are dimensionally compatible with the 2021, provided the offset and center bore also match.
Why is matching the 77.8mm center bore important for the 2021 1500 Classic Regular Cab?
The 77.8mm center bore ensures the wheel is perfectly centered on the hub. If the wheel is lug-centric instead of hub-centric, you may experience steering wheel vibration at highway speeds.
How tight should I torque the lug nuts on a 2021 Ram 1500 Classic Regular Cab?
Refer to your owner's manual for exact specs, but always tighten the 14x1.5 hardware in a star or crisscross pattern. Re-torque after the first 50 miles of driving.
What is the center bore of a 2021 Ram 1500 Classic Regular Cab?
The factory center bore (hub bore) for the 2021 Ram 1500 Classic Regular Cab is 77.8mm. If your aftermarket wheels have a larger hub bore, you will need hub-centric rings to prevent vibration.
How do I measure the bolt pattern on my 2021 Ram?
The 2021 1500 Classic Regular Cab uses a 6x139.7 pattern. For 4, 6, or 8-lug wheels, measure center-to-center across opposite holes. For 5-lug, measure from the center of one hole to the back of the opposite hole.
Need more vehicle fitment data?
Access our complete, raw JSON/CSV database of over 11,000+ vehicles for your next app or project.
Get the Full Dataset