diff --git a/promql/engine.go b/promql/engine.go
index 0ed6fb0cd..007422c64 100644
--- a/promql/engine.go
+++ b/promql/engine.go
@@ -60,10 +60,10 @@ type engineMetrics struct {
 	maxConcurrentQueries prometheus.Gauge
 	queryLogEnabled      prometheus.Gauge
 	queryLogFailures     prometheus.Counter
-	queryQueueTime       prometheus.Summary
-	queryPrepareTime     prometheus.Summary
-	queryInnerEval       prometheus.Summary
-	queryResultSort      prometheus.Summary
+	queryQueueTime       prometheus.Observer
+	queryPrepareTime     prometheus.Observer
+	queryInnerEval       prometheus.Observer
+	queryResultSort      prometheus.Observer
 }
 
 // convertibleToInt64 returns true if v does not over-/underflow an int64.
@@ -230,6 +230,16 @@ func NewEngine(opts EngineOpts) *Engine {
 		opts.Logger = log.NewNopLogger()
 	}
 
+	queryResultSummary := prometheus.NewSummaryVec(prometheus.SummaryOpts{
+		Namespace:  namespace,
+		Subsystem:  subsystem,
+		Name:       "query_duration_seconds",
+		Help:       "Query timings",
+		Objectives: map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001},
+	},
+		[]string{"slice"},
+	)
+
 	metrics := &engineMetrics{
 		currentQueries: prometheus.NewGauge(prometheus.GaugeOpts{
 			Namespace: namespace,
@@ -255,38 +265,10 @@ func NewEngine(opts EngineOpts) *Engine {
 			Name:      "queries_concurrent_max",
 			Help:      "The max number of concurrent queries.",
 		}),
-		queryQueueTime: prometheus.NewSummary(prometheus.SummaryOpts{
-			Namespace:   namespace,
-			Subsystem:   subsystem,
-			Name:        "query_duration_seconds",
-			Help:        "Query timings",
-			ConstLabels: prometheus.Labels{"slice": "queue_time"},
-			Objectives:  map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001},
-		}),
-		queryPrepareTime: prometheus.NewSummary(prometheus.SummaryOpts{
-			Namespace:   namespace,
-			Subsystem:   subsystem,
-			Name:        "query_duration_seconds",
-			Help:        "Query timings",
-			ConstLabels: prometheus.Labels{"slice": "prepare_time"},
-			Objectives:  map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001},
-		}),
-		queryInnerEval: prometheus.NewSummary(prometheus.SummaryOpts{
-			Namespace:   namespace,
-			Subsystem:   subsystem,
-			Name:        "query_duration_seconds",
-			Help:        "Query timings",
-			ConstLabels: prometheus.Labels{"slice": "inner_eval"},
-			Objectives:  map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001},
-		}),
-		queryResultSort: prometheus.NewSummary(prometheus.SummaryOpts{
-			Namespace:   namespace,
-			Subsystem:   subsystem,
-			Name:        "query_duration_seconds",
-			Help:        "Query timings",
-			ConstLabels: prometheus.Labels{"slice": "result_sort"},
-			Objectives:  map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001},
-		}),
+		queryQueueTime:   queryResultSummary.WithLabelValues("queue_time"),
+		queryPrepareTime: queryResultSummary.WithLabelValues("prepare_time"),
+		queryInnerEval:   queryResultSummary.WithLabelValues("inner_eval"),
+		queryResultSort:  queryResultSummary.WithLabelValues("result_sort"),
 	}
 
 	if t := opts.ActiveQueryTracker; t != nil {
@@ -308,10 +290,7 @@ func NewEngine(opts EngineOpts) *Engine {
 			metrics.maxConcurrentQueries,
 			metrics.queryLogEnabled,
 			metrics.queryLogFailures,
-			metrics.queryQueueTime,
-			metrics.queryPrepareTime,
-			metrics.queryInnerEval,
-			metrics.queryResultSort,
+			queryResultSummary,
 		)
 	}