Why Saddle Fit Matters More Than Ever
Every time a rider settles into the saddle, the entire weight of rider and tack is transmitted through a surface area that averages just 100–120 square inches. Any unevenness in that contact zone translates into concentrated pressure points that can pinch soft tissue, restrict shoulder movement, or rub hair away. Over the years I have watched promising young ranch horses sour, and seasoned barrel horses slow their turns, solely because an otherwise excellent saddle was off by a few millimeters in one area. A western saddle pad with shims turns those millimeters into adjustable variables, giving riders real-world control over fit without sending the saddle to a tree-maker or buying a brand-new rig.
How a Western Saddle Pad with Shims Works
Shims are thin inserts—usually made of felt, foam, or neoprene—that slip into pockets sewn into the pad. By adding or subtracting layers, you can “fill the gaps” between saddle and back, allowing the bars of the tree to sit level and distribute weight evenly. The concept is rooted in the long tradition of the saddle blanket, historically used to soften contact and absorb sweat (Wikipedia). Modern shim systems refine that idea, letting riders correct specific issues such as:
- Bridging: where the center of the saddle floats above the back and pressure loads the withers and loins.
- Downhill balance: common in horses built “croup-high,” leading the pommel to drop and the rider to tip forward.
The result is measurable. Pressure-mapping studies presented at trade shows like WESA consistently show a reduction in peak PSI once the correct shim pattern is installed.
Common Scenarios That Call for a Shimmable Pad
• Young horses that are still building topline muscle. Their shape can change month to month, making a permanently flocked saddle a moving target.
• Older mounts suffering muscle atrophy behind the scapula or along the spine.
• Performance horses that bulk up during competition season and slim down in the off-season.
• Horses with asymmetrical shoulders following an injury.
In each of these cases, a fixed-thickness pad might fix the fit one day and create a new problem the next. A pad with shims keeps pace with the horse’s body.
Anatomy of a Quality Corrective Pad
Based on hands-on use and the manufacturer specifications listed below, several design elements separate a reliable corrective pad from a basic blanket:
Pocket Layout. Multiple pockets—usually three up front, three at the center, and sometimes three at the rear—let you move, stack, or remove inserts independently. This front-to-back and side-to-side latitude is essential for balancing both high withers and uneven shoulders.
Material Stack-Up. Most premium models combine a dense inner felt to disperse impact, a breathable wool or fleece lining to manage moisture, and a tough top fabric for abrasion resistance. Wool remains popular because it can absorb up to 30 percent of its weight in sweat without feeling damp, an advantage well demonstrated by Allure Western’s Merino lining.
Wither and Spine Relief. Contoured toplines and cut-out wither notches prevent binding, especially during collection or steep hill work.
An In-Depth Look at Leading Pad Systems
Below are four shim pads I have used, fitted, or observed in professional saddle-fit sessions, along with their standout features.
Toklat T3 Matrix Western Shim Pad. The T3 offers three roomy pockets per side, each pre-loaded with two ¼-inch felt shims. That means you can add up to 1½ inches of lift exactly where it is needed—or run the pad completely flat by removing all inserts. The WoolBack fleece lining is dense yet springy, dispersing pressure while wicking sweat quickly during long trail miles.
Allure Western Shim Saddle Pad. Designed by an Australian saddle fitter, this model keeps weight down and air flow up. A single full-length pocket on each side simplifies loading and avoids ridges under the saddle bars, while 100 percent Merino wool on the underside handles perspiration and reduces static build-up on dry days.
Tough1 Western Shim Pad. A ½-inch neoprene bottom grips the horse so the saddle stays put during quick direction changes—handy for roping or mounted shooting. Six smaller pockets allow granular adjustment, and the water-repellent canvas top brushes clean with a stiff curry.
Diamond Wool Contour Relief Round Pad. Built for barrel saddles, its shortened round skirt frees a horse’s hip during deep turns. The six-pocket system ships with wool shims and features a wither relief notch reinforced by durable leather to reduce stretching over time.
Video Walkthrough: What Contoured Shims Look Like in Action
The Weaver Leather demo above offers a clear look at how contoured felt inserts slide into pockets and how the pad flexes over the spine when the horse rounds its back.
Practical Steps to Shim Like a Pro
1. Start With a Clean Slate. Place the saddle on the horse without any pad and slide your hand under each bar. Note where daylight appears between tree and back.
2. Choose Your Insert Thickness. A single ¼-inch felt shim is usually plenty; stacking more than two per pocket can raise the saddle so high you create new pressure points.
3. Place Shims Forward First. For downhill horses, load the front pockets. For bridging, address the center pockets. Rear shims are rarely needed unless the cantle drops.
4. Re-check by Feel. After tacking up, slide a flat hand under the skirt. You should meet equal resistance from wither to loin on both sides.
5. Test Under Saddle. Ride at a walk and trot for ten minutes, then pull the pad. Sweat patterns should be even and free of dry spots directly beneath the tree.
Maintenance and Ongoing Monitoring
Even the best shim configuration is temporary. Horses gain and lose condition, hair coats thicken in winter, and leather stretches. I make it a habit to pull the shims every few rides, knock loose dust, and give the pad a proper airing. Felt inserts can be misted with a 50/50 vinegar solution to neutralize sweat salts; neoprene bottoms can be hosed clean and hung to drip dry.
Re-check saddle balance any time your horse’s workload changes. After a month off, a gelding that once needed three front shims may go perfectly in one. By staying proactive, you turn a corrective pad into a preventive tool that stops white hairs and sore backs before they start.
Frequently Asked Questions
Will a shim pad fix a saddle that is two tree sizes off?
No. Shims are for fine-tuning, not major reconstruction. If your saddle perches like a rocking horse or digs into the withers bareback, consult a professional fitter.
Do shims make the saddle less stable?
Only if they are installed unevenly or stacked too thick. A well-balanced shim pattern actually improves stability by eliminating gaps that let the tree rock.
Can I use memory foam instead of felt?
Memory foam feels plush but can bottom out under repeated impact. Felt maintains its thickness ride after ride and is easier to trim with scissors for custom shapes.
What if my horse changes shape unevenly?
Add or subtract inserts on each side individually. Most shim pads allow left/right symmetry or asymmetry, which is invaluable after a shoulder injury.
Is a corrective pad legal in competition?
Most Western performance bodies allow shim pads as long as they are not “training devices” like weighted boots. Always check your specific rulebook.
Final Thoughts
In the past decade, I have put thousands of miles on everything from high-headed cutters to low-headed trail buddies, and the same truth holds: a horse that feels good moves better and lasts longer. A quality shim saddle pad is a small investment compared with the vet bills, downtime, and lost performance that follow chronic back soreness. Whether you choose the versatile Toklat T3, the feather-light Allure, the grip-friendly Tough1, or the contoured Diamond Wool, the principle is identical—customize the interface between tree and topline so the horse can focus on the job, not the discomfort.
Listen to your horse, check your sweat marks, and keep a few spare inserts in your tack room. The next time your gelding bulks up before spring branding, you’ll be ready to tweak—rather than replace—your setup and hit the draw with confidence.