You can always use this adaptor to make it a receiver hitch.
https://tinyurl.com/sc5cpuje  I don't think I'd use this adaptor for a 4 bike option.

I ended up swapping my ball hitch for a receiver, as I felt it provided me more options, and reduces the chances of bumping my leg on it (as I have done countless times over the years).

I have a great tray mount rack, which I love!  So easy, and bikes do not contact the van.
https://tinyurl.com/4vxzaz9s

4 bike rack.  https://tinyurl.com/3ssm8t27

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Jeff Palmer
Sent: Monday, August 16, 2021 10:05 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: 4 Bike carriers

Thanks everyone.  I do have a 3 bike carrier for my ball hitch but we are now four so … that increases the cost of the endeavour a bit :)
Jeff

> On Aug 16, 2021, at 8:34 AM, Stephen Grisanti <bike2vcu@YAHOO.COM> wrote:
> 
> Every four-bike hitch rack I’ve seen has been a receiver type, either 2” or 1.25”. You might find a rack for two or even three bikes that bolt into the hole for the ball but it would be unusual. Good luck. 
> 
> Stephen
> 
> Mobile
> 
>> On Aug 15, 2021, at 7:35 PM, Jeff Palmer <w.jeff.palmer@icloud.com> wrote:
>> 
>> Can anyone recommend a 4 bike carrier that works on a ball hitch?  I expect it might need to be secured to the hatch in some way?
>> 
>> Thanks
>> Jeff
>