Gates
Integrated Housing Thermostat

Gates 34858 Engine Coolant Thermostat

Brand Gates 34858
Outlet Outside Diameter .61
Outlet Outside Diameter 1.34
Bolt Hole Quantity 3
Type Integrated housing thermostat
Jiggle Pin Weep Hole Yes
Start to Open Temperature 172
Start to Open Temperature 78
Outlet Inside Diameter .42
Outlet Inside Diameter 1.08
Electric No
9841 1
Check Valve No
Electric No
Jiggle Pin/Check Valve Yes
Number of Bolt Holes 3
Number of Jiggle Pins/Check Valves 1
Number of Seals 1
OE Comparison Rating Oe performance
OE Exact No
Outlet Inside Diameter 1 (in) 1.08
Outlet Inside Diameter 2 (in) .42
Outlet Outside Diameter 1 (in) 1.34
Outlet Outside Diameter 2 (in) .61
Temperature (C) 78
Product line Integrated Housing Thermostat
Fits Acura · 14 vehicles

Integrated housing thermostat. Combines thermostat and housing for a cleaner, simpler cooling-system repair.

OE performance. Built as an aftermarket alternative with accurate temperature regulation.

Jiggle pin weep hole. Helps purge trapped air for steadier coolant flow and control.

Cross-references Dayco 95172, Dorman - OE Solutions 902-5953 and Dorman - OE Solutions 951-172 for the same application. See all 4.

$63.13Free shipping
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Step 1 — Confirm fitment
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Step 2 — Quantity
Order total $63.13
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Free returns within 60 days if it doesn't fit when fitment is verified.

Integrated thermostat housing for OE temperature control

Gates 34858 is an integrated housing thermostat built for accurate engine coolant temperature regulation. It follows OE-style temperature control with a 172 degree start-to-open rating and includes a seal for service replacement on select Acura applications.

Key features

  • Integrated Housing Thermostat design for modern cooling systems
  • Start to open temperature: 172°F (78°C)
  • OE Performance comparison rating
  • Jiggle pin weep hole and jiggle pin/check valve: Yes
  • 3 bolt holes for mounting
  • Electric: No
  • Single seal included
  • Outlet dimensions: 1.34 in and 0.61 in outside diameter; 1.08 in and 0.42 in inside diameter

Product details

Gates Integrated Housing Thermostat 34858 is engineered for vehicles that use a thermostat and housing assembly in one unit. Gates applies its cooling-system research to aftermarket thermostat solutions that match OE-style temperature regulation, helping maintain proper coolant flow and operating temperature. This part cross-references Dayco 95172 and Dorman - OE Solutions 902-5953 for the same application.

Vehicle fitment

  • Fits 2016-2020 Acura MDX, N/A — 172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
  • Fits 2019-2020 Acura RLX, N/A — 172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
  • Fits 2015-2020 Acura TLX, N/A — 172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
  • Fits 2018 Acura RLX, N/A — W/10-Speed Auto. Trans.; 172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat

Common issues this part addresses

  • Engine running too cool or too hot from a worn thermostat
  • Coolant temperature instability during normal driving
  • Leak points at an aging thermostat housing assembly
  • Delayed warm-up caused by a thermostat that no longer opens at the correct temperature
  • Service issues on Acura MDX, Acura RLX, and Acura TLX cooling systems

Installation notes and quality assurance

Verify the OE temperature specification, outlet dimensions, and bolt-hole count before installation. Clean the sealing surfaces thoroughly and inspect the cooling system for contamination or trapped air after service. Gates backs this thermostat housing line with OE-focused engineering and aftermarket coverage for integrated housing applications.

This part fits 14 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelTransmissionLitersCylindersFuel TypePositionNotes
2020AcuraMDX3.5LV6GASN/A172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
2020AcuraRLX3.5LV6GASN/A172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
2020AcuraTLX3.5LV6GASN/A172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
2019AcuraMDX3.5LV6GASN/A172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
2019AcuraRLX3.5LV6GASN/A172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
2019AcuraTLX3.5LV6GASN/A172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
2018AcuraMDX3.5LV6GASN/A172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
2018AcuraRLXAutomatic3.5LV6GASN/AW/10-Speed Auto. Trans.; 172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
2018AcuraTLX3.5LV6GASN/A172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
2017AcuraMDX3.5LV6GASN/A172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
2017AcuraTLX3.5LV6GASN/A172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
2016AcuraMDX3.5LV6GASN/A172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
2016AcuraTLX3.5LV6GASN/A172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
2015AcuraTLX3.5LV6GASN/A172 Degree; OE Temperature; Seal included; Integrated Housing Thermostat
Directly replaces or cross-references 4 part numbers
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
Dayco — 95172Dorman - OE Solutions — 902-5953Dorman - OE Solutions — 951-172193155J2A01