diff --git a/Grid/lattice/Lattice_slicesum_core.h b/Grid/lattice/Lattice_slicesum_core.h
index 63737517..36580f57 100644
--- a/Grid/lattice/Lattice_slicesum_core.h
+++ b/Grid/lattice/Lattice_slicesum_core.h
@@ -131,9 +131,8 @@ template<class vobj> inline void sliceSumReduction_cub(const Lattice<vobj> &Data
 
 
 #if defined(GRID_SYCL)
-template<class vobj> inline void sliceSumReduction_sycl(const Lattice<vobj> &Data, Vector <vobj> &lvSum, const int  &rd, const int &e1, const int &e2, const int &stride, const int &ostride, const int &Nsimd)
+template<class vobj> inline void sliceSumReduction_sycl_small(const vobj *Data, Vector <vobj> &lvSum, const int  &rd, const int &e1, const int &e2, const int &stride, const int &ostride, const int &Nsimd)
 {
-  typedef typename vobj::scalar_object sobj;
   size_t subvol_size = e1*e2;
 
   vobj *mysum = (vobj *) malloc_shared(rd*sizeof(vobj),*theGridAccelerator);
@@ -147,7 +146,7 @@ template<class vobj> inline void sliceSumReduction_sycl(const Lattice<vobj> &Dat
 
   auto rb_p = &reduction_buffer[0];
 
-  autoView(Data_v, Data, AcceleratorRead);
+  // autoView(Data_v, Data, AcceleratorRead);
 
   //prepare reduction buffer 
   accelerator_for2d( s,subvol_size, r,rd, (size_t)Nsimd,{ 
@@ -157,7 +156,7 @@ template<class vobj> inline void sliceSumReduction_sycl(const Lattice<vobj> &Dat
       int so=r*ostride; // base offset for start of plane 
       int ss= so+n*stride+b;
 
-      coalescedWrite(rb_p[r*subvol_size+s], coalescedRead(Data_v[ss]));
+      coalescedWrite(rb_p[r*subvol_size+s], coalescedRead(Data[ss]));
 
   });
 
@@ -180,6 +179,45 @@ template<class vobj> inline void sliceSumReduction_sycl(const Lattice<vobj> &Dat
   }
   free(mysum,*theGridAccelerator);
 }
+
+
+template<class vobj> inline void sliceSumReduction_sycl_large(const vobj *Data, Vector<vobj> &lvSum, const int rd, const int e1, const int e2, const int stride, const int ostride, const int Nsimd) {
+  typedef typename vobj::vector_type vector;
+  const int words = sizeof(vobj)/sizeof(vector);
+  const int osites = rd*e1*e2;
+  commVector<vector>buffer(osites);
+  vector *dat = (vector *)Data;
+  vector *buf = &buffer[0];
+  Vector<vector> lvSum_small(rd);
+  vector *lvSum_ptr = (vector *)&lvSum[0];
+
+  for (int w = 0; w < words; w++) {
+    accelerator_for(ss,osites,1,{
+	    buf[ss] = dat[ss*words+w];
+    });
+
+    sliceSumReduction_sycl_small(buf,lvSum_small,rd,e1,e2,stride, ostride,Nsimd);
+      
+    for (int r = 0; r < rd; r++) {
+      lvSum_ptr[w+words*r]=lvSum_small[r];
+    }
+
+  }
+}
+
+
+template<class vobj> inline void sliceSumReduction_sycl(const Lattice<vobj> &Data, Vector<vobj> &lvSum, const int rd, const int e1, const int e2, const int stride, const int ostride, const int Nsimd)
+{
+  autoView(Data_v, Data, AcceleratorRead); //hipcub/cub cannot deal with large vobjs so we split into small/large case.
+    if constexpr (sizeof(vobj) <= 256) { 
+      sliceSumReduction_sycl_small(&Data_v[0], lvSum, rd, e1, e2, stride, ostride, Nsimd);
+    }
+    else {
+      sliceSumReduction_sycl_large(&Data_v[0], lvSum, rd, e1, e2, stride, ostride, Nsimd);
+    }
+}
+  
+
 #endif
 
 template<class vobj> inline void sliceSumReduction_cpu(const Lattice<vobj> &Data, Vector<vobj> &lvSum, const int &rd, const int &e1, const int &e2, const int &stride, const int &ostride, const int &Nsimd)