diff --git a/routing/payment_lifecycle.go b/routing/payment_lifecycle.go
index 9757afebd..847d2be42 100644
--- a/routing/payment_lifecycle.go
+++ b/routing/payment_lifecycle.go
@@ -6,6 +6,7 @@ import (
 	"time"
 
 	"github.com/btcsuite/btcd/btcec/v2"
+	"github.com/btcsuite/btcd/btcutil"
 	"github.com/davecgh/go-spew/spew"
 	sphinx "github.com/lightningnetwork/lightning-onion"
 	"github.com/lightningnetwork/lnd/channeldb"
@@ -688,6 +689,26 @@ func (p *paymentLifecycle) sendAttempt(
 		return nil, err
 	}
 
+	// If a hook exists that may affect our outgoing message, we call it now
+	// and apply its side effects to the UpdateAddHTLC message.
+	var err error
+
+	p.router.cfg.TrafficShaper.WhenSome(func(ts TlvTrafficShaper) {
+		var newAmt btcutil.Amount
+		var newData []byte
+
+		newAmt, newData, err = ts.ProduceHtlcExtraData(
+			htlcAdd.ExtraData, uint64(htlcAdd.Amount.ToSatoshis()),
+		)
+
+		htlcAdd.ExtraData = newData
+		htlcAdd.Amount = lnwire.MilliSatoshi(newAmt * 1000)
+	})
+
+	if err != nil {
+		return nil, err
+	}
+
 	// Generate the raw encoded sphinx packet to be included along
 	// with the htlcAdd message that we send directly to the
 	// switch.