diff --git a/CHANGELOG.md b/CHANGELOG.md
index cc5f062e..ec93922f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+## v0.6.0 (Unreleased)
+
+- Features: Replace "sync" with "rtu-sync" and "tcp-sync" respectively
+
 ## v0.5.2 (2021-12-05)
 
 - Fix (RTU): Wrong byte count offset when writing multiple coils/registers
diff --git a/Cargo.toml b/Cargo.toml
index 439ed57c..d8a4c0a8 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -25,20 +25,22 @@ socket2 = { version = "0.4.4", optional = true, default-features = false }
 tokio = { version = "1.17.0", default-features = false }
 # Disable default-features to exclude unused dependency on libudev
 tokio-serial = { version = "5.4.1", optional = true, default-features = false }
-tokio-util = { version = "0.7.0", features = ["codec"] }
+tokio-util = { version = "0.7.0", default-features = false, features = ["codec"] }
 
 [dev-dependencies]
 env_logger = "0.9.0"
 futures = "0.3.21"
-tokio = { version = "1.17.0", features = ["net", "macros", "io-util", "rt", "time"] }
+tokio = { version = "1.17.0", features = ["net", "macros", "io-util", "rt-multi-thread", "time"] }
 
 [features]
-default = ["tcp", "rtu"]
-rtu = ["tokio-serial", "futures-util/sink"]
+default = ["rtu", "tcp"]
+rtu = ["futures-util/sink"]
 tcp = ["tokio/net", "futures-util/sink"]
-sync = ["tokio/rt"]
-server = ["futures", "socket2/all", "tokio/macros", "tokio/rt", "tokio/rt-multi-thread"]
-tcp-server-unstable = ["tcp", "server"]
+rtu-sync = ["rtu", "tokio-serial"]
+tcp-sync = ["tcp"]
+server = ["futures"]
+rtu-server = ["rtu", "server", "tokio/macros", "tokio-serial"]
+tcp-server-unstable = ["tcp", "server", "socket2/all", "tokio/macros", "tokio/rt-multi-thread"]
 
 [badges]
 maintenance = { status = "actively-developed" }
@@ -46,7 +48,7 @@ maintenance = { status = "actively-developed" }
 [[example]]
 name = "rtu-client-sync"
 path = "examples/rtu-client-sync.rs"
-required-features = ["rtu", "sync"]
+required-features = ["rtu-sync"]
 
 [[example]]
 name = "rtu-client"
@@ -56,7 +58,7 @@ required-features = ["rtu"]
 [[example]]
 name = "rtu-server"
 path = "examples/rtu-server.rs"
-required-features = ["rtu", "server"]
+required-features = ["rtu-server"]
 
 [[example]]
 name = "tcp-client-custom-fn"
@@ -66,7 +68,7 @@ required-features = ["tcp"]
 [[example]]
 name = "tcp-client-sync"
 path = "examples/tcp-client-sync.rs"
-required-features = ["tcp", "sync"]
+required-features = ["tcp-sync"]
 
 [[example]]
 name = "tcp-client"
@@ -76,4 +78,4 @@ required-features = ["tcp"]
 [[example]]
 name = "tcp-server"
 path = "examples/tcp-server.rs"
-required-features = ["tcp", "server", "tcp-server-unstable"]
+required-features = ["tcp-server-unstable"]
diff --git a/src/client/mod.rs b/src/client/mod.rs
index 937c0dc9..3105b1df 100644
--- a/src/client/mod.rs
+++ b/src/client/mod.rs
@@ -9,15 +9,15 @@ use async_trait::async_trait;
 
 use crate::{frame::*, slave::*};
 
-#[cfg(feature = "sync")]
-pub mod sync;
-
 #[cfg(feature = "rtu")]
 pub mod rtu;
 
 #[cfg(feature = "tcp")]
 pub mod tcp;
 
+#[cfg(any(feature = "rtu-sync", feature = "tcp-sync"))]
+pub mod sync;
+
 /// Transport independent asynchronous client trait
 #[async_trait]
 pub trait Client: SlaveContext + Send + Debug {
diff --git a/src/client/sync/mod.rs b/src/client/sync/mod.rs
index c08f3c8a..6b21c59a 100644
--- a/src/client/sync/mod.rs
+++ b/src/client/sync/mod.rs
@@ -1,14 +1,11 @@
 //! Synchronous Modbus client
 
-// TODO: Add missing documentation
 #![allow(missing_docs)]
 
-/// RTU client connections
-#[cfg(feature = "rtu")]
+#[cfg(feature = "rtu-sync")]
 pub mod rtu;
 
-/// TCP client connections
-#[cfg(feature = "tcp")]
+#[cfg(feature = "tcp-sync")]
 pub mod tcp;
 
 use super::{
diff --git a/src/lib.rs b/src/lib.rs
index c2001ad1..6f8b6103 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -71,8 +71,8 @@
 //! ## Sync TCP client
 //!
 //! ```rust,no_run
-//! # #[cfg(all(feature = "tcp", feature = "sync"))]
-//! # //FIXME: Run doc tests with `--features sync` to fix failure
+//! # #[cfg(feature = "tcp-sync")]
+//! # //FIXME: Run doc tests with `--features rtu-sync,tcp-sync` to fix failure
 //! pub fn main() -> Result<(), Box<dyn std::error::Error>> {
 //!     use tokio_modbus::prelude::*;
 //!
@@ -114,8 +114,8 @@
 //! ## Sync RTU client
 //!
 //! ```rust,no_run
-//! # #[cfg(all(feature = "rtu", feature = "sync"))]
-//! # //FIXME: Run doc tests with `--features sync` to fix failure
+//! # #[cfg(feature = "rtu-sync")]
+//! # //FIXME: Run doc tests with `--features rtu-sync,tcp-sync` to fix failure
 //! pub fn main() -> Result<(), Box<dyn std::error::Error>> {
 //!     use tokio_modbus::prelude::*;
 //!
diff --git a/src/prelude.rs b/src/prelude.rs
index 91ea8004..135ff036 100644
--- a/src/prelude.rs
+++ b/src/prelude.rs
@@ -29,6 +29,12 @@ pub mod tcp {
 #[cfg(feature = "server")]
 pub use crate::server;
 
+#[allow(missing_docs)]
+#[cfg(any(feature = "rtu-sync", feature = "tcp-sync"))]
+pub mod sync {
+    pub use crate::client::sync::*;
+}
+
 ///////////////////////////////////////////////////////////////////
 /// Structs
 ///////////////////////////////////////////////////////////////////
@@ -40,13 +46,13 @@ pub use crate::slave::{Slave, SlaveId};
 ///////////////////////////////////////////////////////////////////
 pub use crate::client::{Client, Reader, Writer};
 
-#[cfg(feature = "sync")]
+#[cfg(any(feature = "rtu-sync", feature = "tcp-sync"))]
 pub use crate::client::sync::Client as SyncClient;
 
-#[cfg(feature = "sync")]
+#[cfg(any(feature = "rtu-sync", feature = "tcp-sync"))]
 pub use crate::client::sync::Reader as SyncReader;
 
-#[cfg(feature = "sync")]
+#[cfg(any(feature = "rtu-sync", feature = "tcp-sync"))]
 pub use crate::client::sync::Writer as SyncWriter;
 
 pub use crate::slave::SlaveContext;
diff --git a/src/server/mod.rs b/src/server/mod.rs
index d71d5380..ad35ea7e 100644
--- a/src/server/mod.rs
+++ b/src/server/mod.rs
@@ -3,7 +3,7 @@
 // TODO: Add missing documentation
 #![allow(missing_docs)]
 
-#[cfg(feature = "rtu")]
+#[cfg(feature = "rtu-server")]
 pub mod rtu;
 
 #[cfg(feature = "tcp-server-unstable")]