diff --git a/components/zcash_address/src/kind/unified/f4jumble.rs b/components/zcash_address/src/kind/unified/f4jumble.rs
index 4d346076e..84c86014f 100644
--- a/components/zcash_address/src/kind/unified/f4jumble.rs
+++ b/components/zcash_address/src/kind/unified/f4jumble.rs
@@ -4,6 +4,8 @@ use std::ops::RangeInclusive;
 
 #[cfg(test)]
 mod test_vectors;
+#[cfg(test)]
+mod test_vectors_long;
 
 const VALID_LENGTH: RangeInclusive<usize> = 48..=4194368;
 
@@ -121,10 +123,13 @@ pub fn f4jumble_inv(c: &[u8]) -> Option<Vec<u8>> {
 
 #[cfg(test)]
 mod tests {
+    use blake2b_simd::blake2b;
     use proptest::collection::vec;
     use proptest::prelude::*;
 
-    use super::{f4jumble, f4jumble_inv, test_vectors::test_vectors, VALID_LENGTH};
+    use super::{
+        f4jumble, f4jumble_inv, test_vectors::test_vectors, test_vectors_long, VALID_LENGTH,
+    };
 
     #[test]
     fn h_pers() {
@@ -170,4 +175,15 @@ mod tests {
             assert_eq!(unjumbled, v.normal);
         }
     }
+
+    #[test]
+    fn f4jumble_check_vectors_long() {
+        for v in test_vectors_long::TEST_VECTORS {
+            let normal: Vec<u8> = (0..v.length).map(|i| i as u8).collect();
+            let jumbled = f4jumble(&normal).unwrap();
+            assert_eq!(blake2b(&jumbled).as_bytes(), v.jumbled_hash);
+            let unjumbled = f4jumble_inv(&jumbled).unwrap();
+            assert_eq!(unjumbled, normal);
+        }
+    }
 }
diff --git a/components/zcash_address/src/kind/unified/f4jumble/test_vectors_long.rs b/components/zcash_address/src/kind/unified/f4jumble/test_vectors_long.rs
new file mode 100644
index 000000000..ccc39139d
--- /dev/null
+++ b/components/zcash_address/src/kind/unified/f4jumble/test_vectors_long.rs
@@ -0,0 +1,28 @@
+pub(crate) struct TestVector {
+    pub(crate) length: usize,
+    pub(crate) jumbled_hash: &'static [u8],
+}
+
+// From https://github.com/zcash-hackworks/zcash-test-vectors/blob/master/f4jumble_long.py
+pub(crate) const TEST_VECTORS: &[TestVector] = &[
+    TestVector {
+        length: 3246395,
+        jumbled_hash: &[
+            0x3f, 0xc2, 0xec, 0xdf, 0xb6, 0x86, 0x96, 0x57, 0x1d, 0x89, 0xe8, 0xbe, 0xdd, 0xb6,
+            0x47, 0xe6, 0x99, 0x0b, 0x63, 0xa0, 0x17, 0x1c, 0x36, 0x44, 0x22, 0x73, 0xd6, 0x87,
+            0xbd, 0x99, 0x25, 0x7e, 0xc5, 0x00, 0x2e, 0xc8, 0x19, 0x78, 0x01, 0xb6, 0x21, 0x73,
+            0x2d, 0x6b, 0x05, 0xb8, 0xd7, 0x0f, 0x68, 0x86, 0x20, 0xa4, 0xc0, 0x88, 0x73, 0xc1,
+            0x2e, 0x44, 0x39, 0xa0, 0x12, 0x7d, 0xc9, 0x45,
+        ],
+    },
+    TestVector {
+        length: 4194368,
+        jumbled_hash: &[
+            0xa5, 0xf1, 0x8f, 0x16, 0x3e, 0x59, 0x8d, 0x4a, 0xdb, 0x6e, 0xa7, 0x24, 0x80, 0x57,
+            0xe2, 0x4c, 0x1b, 0x61, 0xf2, 0x9b, 0x33, 0xb7, 0xab, 0xcd, 0xab, 0xd4, 0x20, 0xa0,
+            0xf2, 0xee, 0x6c, 0x3e, 0xd3, 0x13, 0x94, 0x65, 0x2f, 0x28, 0xb5, 0x9c, 0x44, 0xd3,
+            0xea, 0x9e, 0xcf, 0x85, 0xf4, 0xd5, 0x01, 0xe6, 0xaa, 0xc1, 0x4d, 0xf2, 0x88, 0xef,
+            0xd6, 0x2c, 0xf8, 0x0d, 0x18, 0x29, 0xd0, 0x25,
+        ],
+    },
+];