diff --git a/.changeset/shaggy-sheep-pull.md b/.changeset/shaggy-sheep-pull.md
new file mode 100644
index 00000000000..9c4ac23123b
--- /dev/null
+++ b/.changeset/shaggy-sheep-pull.md
@@ -0,0 +1,5 @@
+---
+"@apollo/client": patch
+---
+
+`QueryManager.transformCache`: use `WeakCache` instead of `WeakMap`
diff --git a/.size-limits.json b/.size-limits.json
index ee06be421b2..203fbb531d2 100644
--- a/.size-limits.json
+++ b/.size-limits.json
@@ -1,4 +1,4 @@
 {
-  "dist/apollo-client.min.cjs": 38625,
-  "import { ApolloClient, InMemoryCache, HttpLink } from \"dist/index.js\" (production)": 32203
+  "dist/apollo-client.min.cjs": 38630,
+  "import { ApolloClient, InMemoryCache, HttpLink } from \"dist/index.js\" (production)": 32213
 }
diff --git a/src/core/QueryManager.ts b/src/core/QueryManager.ts
index 98ab4d1d1f4..f6c471ef840 100644
--- a/src/core/QueryManager.ts
+++ b/src/core/QueryManager.ts
@@ -4,6 +4,7 @@ import type { DocumentNode } from "graphql";
 // TODO(brian): A hack until this issue is resolved (https://github.com/graphql/graphql-js/issues/3356)
 type OperationTypeNode = any;
 import { equal } from "@wry/equality";
+import { WeakCache } from "@wry/caches";
 
 import type { ApolloLink, FetchResult } from "../link/core/index.js";
 import { execute } from "../link/core/index.js";
@@ -27,7 +28,6 @@ import {
   hasClientExports,
   graphQLResultHasError,
   getGraphQLErrorsFromResult,
-  canUseWeakMap,
   Observable,
   asyncMap,
   isNonEmptyArray,
@@ -651,10 +651,10 @@ export class QueryManager<TStore> {
     return this.documentTransform.transformDocument(document);
   }
 
-  private transformCache = new (canUseWeakMap ? WeakMap : Map)<
+  private transformCache = new WeakCache<
     DocumentNode,
     TransformCacheEntry
-  >();
+  >(/** TODO: decide on a maximum size (will do all max sizes in a combined separate PR) */);
 
   public getDocumentInfo(document: DocumentNode) {
     const { transformCache } = this;