1961–1966 Ford F-100 — Slickside

Fits · 1961–1966 only — this IS the generation guide

The Slickside is two trucks in one generation: 1961–64 on the early front suspension, 1965–66 on Twin I-Beam — with the integrated “unibody” Styleside in the early years. Get that split right and everything else in this guide falls into place.

Generation Notes

Build philosophy: Prioritize stance, steering, brakes, and wheel fitment. Keep the original frame and running engine where practical; expensive swaps should be a deliberate choice, not the first step.

This group has an important mid-generation change: 1961–1964 trucks use the earlier front suspension layout, while 2WD F-100s gained Twin I-Beam suspension for 1965. Also verify whether a 1961–1963 truck has the integrated Styleside body, which affects body repair and bed decisions but does not mean the truck lacks a frame.

The integrated cab-and-bed Styleside (“unibody”) design was offered 1961–1963 — and a conventional separate-cab Styleside was also available alongside it from 1962; the unibody was dropped partway through 1963, and 1964 was separate cab and bed only. Twin I-Beam arrived for 2WD F-100s in 1965. Four-wheel-drive trucks use a different front setup.

Best DIY Modifications

1961–1964 front suspension

Planning cost: $700–$1,800+ for dropped axle options; roughly $1,500–$3,500+ for an IFS conversion before major labor.

These years should not automatically be treated like 1965–1966. Confirm the actual front axle/suspension and use a kit intended for that configuration.

1965–1966 Twin I-Beam lowering

Planning cost: $450–$1,200 for lowering and supporting front parts.

Purpose-built drop beams or other application-specific parts may retain the original Twin I-Beam layout. Confirm steering geometry, shock travel, tire clearance, and alignment.

Rear lowering

Planning cost: $150–$600 for basic parts; more with clearance work.

A matched rear spring/block setup can give a mild drop; more aggressive setups require careful bump-stop and driveshaft checks.

Crown Victoria front swap

Planning cost: $1,200–$3,000+ DIY depending on fabrication.

Possible as a custom project, not a bolt-in kit. Frame mounts, track width, steering, brakes, wheel bolt pattern, and engine clearance all need engineering.

Engine Swap Options

Engine / route	Approx. DIY parts cost	Pros & compatibility notes
240/300 inline-six (1965–1966 era)	$500–$2,500 for used engine/refresh parts	A healthy 300 is a durable, torque-oriented choice. Earlier trucks may have different original engines, so verify mounts and transmission.
302 Windsor	$1,000–$3,500 for used engine and basic conversion parts	Popular small-block swap, but check mounts, oil pan, cooling, exhaust, transmission, and driveshaft.
351 Windsor	$1,500–$4,000 for engine and basic parts	More displacement, with packaging and drivetrain checks required.
Coyote 5.0	$10,000–$18,000+ for a DIY parts build	High-end route; full electronics, transmission, fuel, cooling, exhaust, and fabrication budget required.

Engine cost ranges are broad planning estimates, not installed quotes. They exclude many labor, shipping, tax, and troubleshooting costs. Identify the engine and transmission actually in the truck before purchasing swap parts.

Coyote figure corrected — Oct 2026 fact-check. Earlier drafts of this guide priced a DIY Coyote conversion at $8,000–$15,000+. Street Trucks’ F-100 Coyote cost research puts a parts-only DIY build around a used F-150 pullout at roughly $10,000–$18,000 — before the Ford Performance control pack (~$2,100–$2,730) that the swap also needs. A running pullout plus transmission can consume most of $8,000 before mounts, fuel, cooling, and wiring, so the table above uses the corrected range.

Example Budget

Item	Planning budget
Front lowering / conversion allowance	$450–$1,800
Rear lowering and shocks	$200–$600
Steering/brake refresh allowance	$350–$900
Wheels and tires	$600–$1,400
Alignment, fluids, hardware	$200–$500
Planning total (not a quote)	$1,800–$5,200+

Budget assumptions. Assumes a usable frame, a running engine/transmission, mostly DIY labor, and no major rust or structural repair. The total is an initial planning range — not a guaranteed all-in cost. A complete brake conversion, custom fabrication, frame notch, or professional welding can increase the price.

Build Order

Recommended build sequence

1 · Identify the truck. Confirm model year, 2WD/4WD, wheelbase/bed, engine, transmission, axle, and any prior modifications.
2 · Inspect before buying. Check frame rust, steering mounts, suspension pivots, brakes, wheel bearings, fuel lines, and driveline condition.
3 · Choose the target stance. Decide mild versus aggressive drop, and plan front/rear heights together.
4 · Select compatible suspension parts. Use year-specific fitment and verify travel, geometry, bump stops, brake hoses, and driveshaft angles.
5 · Confirm wheel fitment. Check bolt pattern, width, offset/backspacing, brake clearance, and tire clearance at full steering lock and suspension travel.
6 · Align and test safely. Verify steering, braking, suspension travel, and driveline behavior before daily use.

Recommended starting build

Before buying parts, identify the exact year and whether it is 2WD or 4WD. The 1961–1964 and 1965–1966 front suspension choices differ substantially; 1961–1963 integrated-body trucks also deserve a careful body/frame inspection.

Safety.

Use rated jack stands; never work under a truck supported only by a jack. Structural welding and critical suspension mounts should be completed or inspected by a qualified fabricator. Brake and steering modifications must be properly engineered and tested before road use.

Parts list — shop this generation’s build

Built from this guide’s own sections. Links are marked affiliate slots until each retailer program approves F100 Restomod — hard parts route to CJ Creators / JEGS, tools and consumables to Amazon, donor and used parts to eBay Partner Network. Fat Fender Garage and QA1 run no affiliate programs, so they appear as name-only mentions.

’61–’64: dropped front axle — JEGS · CJ CreatorsAffiliate slot
’61–’64: Mustang II-style IFS conversion kit — JEGS · CJ CreatorsAffiliate slot
’65–’66: DJM Dream Beams (kingpin design) — JEGS · CJ CreatorsAffiliate slot
’65–’66: tie-rod relocation kit — JEGSAffiliate slot
Rear lowering blocks / lowering springs — JEGS · CJ CreatorsAffiliate slot
Crown Victoria front clip, 2003–11 (donor — custom swap) — eBay Partner NetworkAffiliate slot
’73–’79 disc spindles for ’65–’66 beam trucks (donor) — eBay Partner NetworkAffiliate slot
Drop shocks, front & rear — JEGS · CJ CreatorsAffiliate slot

The list splits at 1965, exactly like the guide: ’61–’64 parts are straight-axle parts; ’65–’66 parts are Twin I-Beam parts. Ordering across that line is the most expensive mistake in this generation.

Reference Notes

Use these references for generation history and specific installation context. Parts compatibility and prices must be confirmed with the manufacturer/supplier for the exact truck. Some linked guides are historical and should be treated as starting points, not substitutes for current installation instructions.

F-100 generation history and Twin I-Beam timing: supermotors.net/registry/ford/f-100
1961–1966 chassis, unibody, and engine overview: supermotors.net/registry/ford/f-100/1961-1966
1953–1956 Mustang II crossmember instructions: static.speedwaymotors.com/pdf/910-34425.pdf
1953–1956 rear axle/lowering discussion: ford-trucks.com — 1953–1956 F100 rear end selection
1965–1979 IFS / Twin I-Beam overview: Classic Truck Performance, July 2024

All dollar figures are rough U.S. planning estimates and can vary substantially with donor condition, parts availability, fabrication, shipping, and the amount of work done at home.