Failed Your MOT for a Split CV Boot? Here’s What It Actually Looks Like
If you’ve recently failed your MOT because of a split CV boot, you’re not alone. It’s one of those faults that many drivers have never heard of until it appears on their MOT certificate.
At Lindleys Autocentres, we carry out thousands of MOT tests every year across Nottinghamshire and regularly see vehicles fail with the following defect:
Drive shaft joint constant velocity boot split or insecure, no longer prevents the ingress of dirt (6.1.7 (g) (ii))
While that wording might sound complicated, the issue is actually quite straightforward
What Is a CV Boot?
A CV (Constant Velocity) boot is a flexible rubber cover fitted over the CV joint on your driveshaft.
Its job is to:
- Keep grease inside the CV joint.
- Prevent water, grit and road dirt from getting in.
- Protect the moving parts from premature wear.
Although it’s only a rubber boot, it performs a vital job. Once it splits, the grease begins to escape and contaminants can enter the joint.
What Does a Split CV Boot Look Like?
These are all genuine examples we’ve found during MOT inspections.
Small Split Starting to Leak
Even though the damage doesn’t look severe, you can already see grease escaping from the boot.
Once grease begins to leak out, the seal has been compromised and dirt can start working its way inside the joint.
Small split beginning to leak grease
Grease Escaping Around the Joint
This boot has split around the larger end where it attaches to the CV joint.
The escaped grease is a clear indication that the boot is no longer providing adequate protection.
Split around the outer CV joint allowing grease to escape
Early Signs Many Drivers Never Notice
From underneath the vehicle it’s easy to spot grease collecting around the damaged section of the boot.
From outside the car, however, most drivers would never know there was a problem until the MOT inspection.
Early-stage CV boot failure found during an MOT inspection
Left Too Long
In this example the boot has split across several folds and a significant amount of grease has escaped.
At this stage there’s a much greater chance that dirt and water have already entered the CV joint, increasing the likelihood of more expensive repairs.
Severely split outer CV boot requiring immediate repair
Why Does a Split CV Boot Fail an MOT?
Many people assume the failure is because the rubber has cracked.
That’s only part of the story.
The actual MOT failure is because the damaged boot no longer prevents the ingress of dirt.
Once the protective seal is broken:
- Grease escapes.
- Dirt and water enter the CV joint.
- Internal components begin to wear.
- The joint can eventually become noisy or fail altogether.
The MOT is designed to identify this before the damage becomes much more expensive.
Can You Drive With a Split CV Boot?
If you’ve just failed your MOT because of a split CV boot, the safest option is to have it repaired as soon as possible.
While the vehicle may still be driveable depending on the severity of the damage, every mile driven with a split boot increases the chance of contamination reaching the CV joint.
If the joint itself becomes worn, what could have been a relatively straightforward CV boot replacement may become a much more expensive CV joint or driveshaft replacement.
Can a Split CV Boot Be Repaired?
In many cases, yes.
If the CV joint hasn’t been damaged, replacing the boot and replenishing the grease is often all that’s required.
However, if the joint has already worn due to contamination, replacing the complete CV joint or driveshaft may be the more reliable repair.
Our technicians will always inspect the joint itself before recommending the most appropriate solution.
Book an MOT or Vehicle Inspection
If your MOT has highlighted a split CV boot, or you’ve noticed grease around one of your front wheels, it’s worth having the vehicle inspected before the damage becomes more extensive.
At Lindleys Autocentres, our experienced technicians carry out MOT testing and repairs across Nottinghamshire, helping drivers keep their vehicles safe, reliable and roadworthy.
Whether it’s a split CV boot, worn suspension components or another MOT failure, we’ll explain the issue in plain English and recommend the most appropriate repair.
If your vehicle has failed its MOT due to a split CV boot, our experienced technicians can inspect the damage, carry out any necessary repairs and get you safely back on the road. Whether you need an MOT, repair or routine car servicing, contact your nearest Lindleys Autocentres branch or book online today.
