* Broken or damaged door latch mechanism: This is the most likely culprit. The latch itself might be broken, or the linkage connecting the handle to the latch might be bent, worn, or disconnected. This prevents the door from latching properly.
* Worn or broken door striker: This is the metal piece on the door frame that the latch engages with. If it's bent, broken, or worn down, the latch won't engage securely.
* Bind in the door hinges: Over time, hinges can become stiff or rusty, making it hard to open the door. This is less likely to be the *sole* cause if the door won't stay up, but could contribute.
* Issues with the door regulator (if power windows): If you have power windows and locks, a problem with the regulator could indirectly affect the door's ability to close and stay closed. However, this is less likely to be the primary issue if the door is hard to open manually.
* Problems with the door handle: A broken or damaged interior or exterior door handle could hinder the door's operation. This also makes it more likely you are struggling to pull the door open.
Troubleshooting Steps:
1. Inspect the latch mechanism: Open the door (if possible) and carefully examine the latch mechanism itself. Look for any broken parts, bent linkages, or anything out of place. You might need a flashlight to get a good look.
2. Check the door striker: Inspect the striker plate on the door frame. Look for damage, wear, or misalignment. Sometimes, the striker can become loose or pulled out of alignment.
3. Lubricate the hinges: Apply a penetrating lubricant (like WD-40 or a silicone-based spray) to the hinges. Work the door back and forth gently several times to distribute the lubricant. This won't solve a broken latch, but will help if hinge stiffness is a contributing factor.
4. Check the door handle: Try opening the door from both the inside and outside handles to determine if the problem is isolated to one handle or is a more comprehensive latch mechanism issue.
5. Check for Obstructions: Ensure nothing is blocking the door from closing properly. Sometimes a child's toy or other object can get caught and prevent the latch from engaging.
If you're not comfortable working on your car yourself:
Take your Tahoe to a mechanic. They have the tools and experience to diagnose the problem accurately and repair it. Describing the symptoms ("door hard to open, won't stay closed unless propped up") will help them pinpoint the likely cause. This is the safest approach if you're unsure of the cause.
