Rear Spare Tire Support Plate Shock Mount Crossmember - Heavy Duty Fit

In this review the Mountainpeak rear spare tire support plate is examined for owners of 1999-2014 Chevrolet Silverado and GMC Sierra 1500 trucks who need a stronger, corrosion-resistant crossmember. The bottom line: this is a straightforward replacement that focuses on durability and fit, replacing the crossmember that sits forward of the rear axle and supports the rear of the fuel tank and the upper left shock. It is best for owners who want a beefier, galvanized steel part that welds in place and restores the factory mounting geometry.

Key Features

• Fitment: Designed specifically for 1999-2006 Silverado/Sierra and 2007-2014 Silverado 1500 and GMC Sierra 1500 Reg Cab, Ext Cab, and Crew Cab, ensuring correct alignment with original frame mounts.
• Heavy duty material: Constructed from heavy duty steel with a galvanized surface to resist rust and provide a better welding surface than untreated parts.
• Easy to install: Installation avoids full bed removal; remove the old shock, position the replacement crossmember, weld it solid, then reinstall the fuel tank and shocks.
• Function: Runs side to side on the frame to support the upper left side shock and the rear end of the gas tank, restoring original support and load path.
• Included plates: Two outer end plates and a right side inside mount plate are sent loose to simplify fitting and final welding during installation.

Who It's For

This part is for truck owners, mechanics, and restoration projects where the original spare tire support crossmember is corroded, damaged, or weakened and a solid replacement is needed. It suits those comfortable with basic frame welding and reinstallation of the fuel tank and shocks.

It is not ideal for someone seeking a bolt-in, non-permanent fix or a solution that requires no welding; if you need a no-weld repair or a different fitment outside the listed years and cab types, look for alternate options.

Pros & Cons

Pros

• Build quality is noticeably beefier than many factory units, giving improved durability under load.
• Galvanized surface improves corrosion resistance compared to bare steel and prepares the part for welding.
• Correct fitment for a wide range of 1999-2014 Silverado and Sierra 1500 models, which reduces trial-and-error during installation.
• Loose end plates simplify alignment and welding on the bench or frame.

Cons

• Requires welding and basic frame work; not a bolt-in replacement for users without welding equipment.
• Instructions are minimal in the listing, so installers should be comfortable with fuel tank removal/reinstallation procedures.

Specifications

Brand	Mountainpeak
Fitment Years	1999-2006 and 2007-2014 Silverado/Sierra 1500
Compatible Cab Types	Reg Cab, Ext Cab, Crew Cab
Material	Heavy duty steel, galvanized surface
Function	Rear spare tire support crossmember that supports upper left shock and rear of gas tank
Included Parts	Crossmember plus two outer end plates and one right side inside mount plate

Our Verdict

For Silverado and Sierra 1500 owners who need a robust, long-lasting replacement crossmember, this Mountainpeak spare tire support plate is a practical choice. It delivers improved build quality and corrosion protection and restores proper support for the fuel tank and rear shock, offering good value when a welded repair or replacement is acceptable.

Frequently Asked Questions

Will this fit my 2005 Silverado?
Yes, the support plate lists fitment for 1999-2006 Chevrolet Silverado 1500 models, so it is compatible with a 2005 Silverado when installed as described.

Does this require welding to install?
Yes, the crossmember is designed to be set in place and welded solid; two outer end plates and an inside mount plate are provided loose to aid welding and alignment.

Is the surface treated to resist rust?
The part has a galvanized surface which improves anti-rust properties and provides a better welding effect than untreated steel.