Review: Grand Design Momentum 399
As we mentioned in the video, we wanted to do a written review of the Grand Design Momentum 399 so we could continuously update and be more thoughtful. This way, it will be easier to answer questions and update too.
Let’s start with the biggest pros, cons and would we buy it again?
- It’s stunning and everyone loves it!
- A second bathroom (we should stop here)
- Side deck for working out, wet dog or just chilling out
- 3 axles for higher weight capacity, which means full water is not a problem
- 3 AC units keep the rig cool on hot days
- We never run out of hot water with a 12 gal hot water heater
- The shower is great. Everyone invites us to their house for “nice hot shower”, we have one 🙂
- The onboard gen is a “Get out of jail free” card
- Easier to maneuver than people think. With a long bed truck, 92-degree turning radius
- With the Kodiak Hydraulic Brakes, it stops on a dime
- Unlimted power with the Battle Born Batteries setup
- It’s big so it’s always on your mind
- Toy Haulers are not as “homey” as other RVs
- Height is always a concern when driving
- More axles, more tires, more money
- The Lippert One Control is a pain to operate
- More systems, more to keep up with
- Setup and teardown take longer
- The 399 does not have access to the master bedroom or fridge when traveling
- The curved master bed requires a custom mattress
Would we buy the Grand Design Momentum 399 again?
Short answer: Yes.
Medium answer: We think a Toy Hauler is best for a couple with a motorcycle or a couple that wants a large office in the back. Using it as a “teen hauler” has some drawbacks. First, the garage becomes a collect-all/storage area and combined with the kids living quarters, it seems to always be messy. If we were to do it again, we would find a large 5th wheel bunkhouse and remove the jungle gym that RV manufacturers like to install and replace it with two standard twin beds (like I love Lucy) and a small end table in the middle with a lamp. If you have younger kids or Grandkids, the standard bunkhouses are fine, but when kids get over 5.5″ the narrow bunks and low headspace becomes a problem (for fulltime usage). Weekend trips are fun and no one cares!
Long answer: We have had good luck with Grand Design. They handle warranty issues quickly and have an easy to use customer service email. We have had parts mailed directly to us at RV parks and installed ourselves. They have even offered to reimburse us for mobile techs to avoid going to a dealer.
When traveling with a large rig, it requires a lot of attention. If you’re the kind of RVer that enjoys the RV as much as the destination, this is not a problem. But if your RV is just a means to go hiking, visit National Parks, etc. then you might not enjoy “dealing” with your RV so much. With that being said, I enjoy fussing with the RV, t0wing it and appreciate that aspect of RVing too. If you’re willing to travel with a big rig, then you get to enjoy more space when you arrive.
Some people commented that this season seemed fatiguing for us. Yes, between getting stuck in the mud, getting caught on telephone wires, almost breaking our stabilizers and doing all the upgrades… there was a lot going on. Yet, this is what happens when you travel fulltime. It’s no different than the 3 flat tires we had during Season 1, losing Caleb’s laptop to a slide leak, dog tracking to Mexico with a missing center pin, resecuring our front end cap on, or almost dropping Grand Ginger because I forgot to lower the tongue jack.
RVing is the best way to travel because we have our own bed and coffee maker, but it’s also an adventure. It can be dangerous if your head isn’t in the game and that’s what makes it exciting. The reason we change RVs so frequently is so we can stay in “learning mode”. Learning and sharing is what keeps us interested.
Toy Ginger and the Ford F450 have already been sold to a nice couple in OR that is going fulltime and running their business from the road. We couldn’t be happier that this amazing RV is going to long-time subscribers.
Season 8 starts on January 12th with a reveal video of the latest Ginger! Stay tuned. It’s going to be a great season… with more learning!
Complete List of all Toy Gingers Upgrades & Modifications
On this page, we’ll be sharing all the upgrades we complete on the 2019 Ford F450 and 2019 Grand Design Momentum 399TH. As we mentioned in the video, we’ll be using Toy Ginger for the duration of Season 7, sharing what we learn, debugging any issues (and there’s been a few), adding the upgrades and then selling the entire rig at the end of Season 7!
We don’t know if this plan is 100% sustainable yet, but as you have seen, we act quickly on our crazy ideas! Already we’ve learned so much about GPS route apps and Tricia has created all sorts of new organization ideas for the RV. When we’re in “learning mode”, we’re sharing even more; making the process of documenting our travel that much more rewarding.
The first decision we had to make was which 5th wheel hitch to use. Because we’re new to fifth wheels and Toy Ginger’s GVWR of 20,000 pounds, we elected to go with the B&W Companion hitch with the OEM puck system. This is what JD from Big Truck Big RV recommended and etrailer.com also thought it was the best option for us.
Pros & Cons: Now that we’ve been using the hitch for 5,000 miles, I love the sturdiness and simplicity of the hitch. There is ZERO play and connecting/disconnecting is a breeze. What are the drawbacks? If you’re not full-time RVing, you may not be willing to give-up the bed of your truck. It takes me about 5 min to remove the hitch from the bed. For even faster removal, you can look into the B&W Companion hitch that connects to the turnover ball or use a gooseneck hitch. Whichever hitch you decide to buy, be sure to check the weight ratings.
We have an affiliate link with etrailer.com. When it comes to big purchases for the truck and RV, we wanted to provide a resource that not only supports the KYD community but provides additional support and education.
ProClip Cell Phone Holder
This item came highly recommended through the comments and now I know why! This is a solid phone holder from ProClip. This is not an affiliate link, but KYD10 will save you 10%. They are a bit pricy compared to generic models, but because each cell phone holder is custom to your phone and truck, they actually work.
There are a couple of models to choose from and I suggest not getting the angled one. There is still plenty of angel with the model that faces forward. It does look a bit bulky with the bar that goes across the dash, but it’s not a problem.
Depending on your state, mud flap on dual-wheel drive trucks are required, but regardless mudflaps are a good idea and the F450 looked naked without them. I wanted a streamlined factory look and the WeatherTech no-drill mud flap was the best option.
These mud flaps fit perfect using the existing holes and no drilling. Be sure to add your truck to the etrailer website and find the right pair.
The BAKFlip tonneau cover is one of my favorite upgrades. I was very eager to get it installed on the new truck. Not until we got a 5th wheel did we know about the drawback not being able to see the hitch (from over my shoulder) when backing up.
This makes the BAKFlip MX4 my favorite bed cover for a travel trailer, but probably wouldn’t get it again if I had a 5th wheel. Which says a lot because I really love these bed covers. The fact is, the 5th wheel cam just isn’t adiquite and more times than not is overexposed due to the angle of the sun. I’ll be doing some reserch on the best bed cover for 5th wheel towing and post to our etrailer.com page.
Airlift QuickShot Compressor System for Air Springs
As I mentioned in the video, the Ford F450 only squats a little even with a heavy load, but I wanted the truck and trailer to be perfectly level. I also wanted on-board air to make adding air to our 12 110 PSI tires easy.
I was very happy with the install that Max-Bilt did in Eau Claire, WI. The location of the air switch in the upper glove box is perfect. The only thing I’m not pleased with is the Schrader valve appose to a quick disconnect with my previous ViAir system. If you don’t have the need for on-board air, consider the ViAir pump which is small and highly effective for tires over 65 psi.
TST Tire Pressure Monitor System
The Ford F450 doesn’t come with a built-in TPMS system. We use the TST TPMS system from TST provided by TechnoRV. This system allows us to add all six tires on the RV and the truck and the tire pressure for each tire are displayed on a color screen on our dash. As we drive, each tire rotates through on the screen. If there is a problem or the tire pressure falls below or exceeds the parameters I set, an alarm will sound.
This is by far the best TPMS system we’ve used and we’ve used them all. The cheap ones simply are not reliable and others are not easy to use. If you buy a TPMS system from TechnoRV, you’ll receive instructional videos on how to set up and install. They will also provide support should you have any issues.
Aire-Flow Moisture Barrier by Mattress Insider
First of all, don’t forget that Mattress Insider provides the KYD Community 10% off with the promo code KYD10.
We heard in the comments during Season 1 that due to the varying temperatures in an RV that moisture or even mold can build below a memory foam mattress. The Aire-Flow Moisture Barrier prevents that. It comes in a roll and you can cut it to size.
50 Amp Surge Gaurd
We stared with a cheap Camco surge protector when we first started and worked our way up. Considering all the electrical systems in a Grand Design Momentum 399, total protection is key. The Surge Guard is the best and completes an analysis of the connection for 10 seconds prior to sending power to your RV
Lithium Battery Solar Upgrade
We kill lead-acid batteries. We don’t want to, but managing distilled water levels just isn’t on our mind when traveling fulltime and making videos. We also don’t do a good job keeping the battery above 50% capacity. These worries are gone when upgrading to Lithium. Yes, Battle Born Batteries are $1,000 each but if you plan on keeping your RV for a while, you’ll avoid paying for lead-acid batteries two or three times over. *Maybe you’re better at maintaining things than me!
We also added 1,200 watts of solar on the roof with a 3,000 watt Victron Mult-plus invertor. You can watch the install video here.
Kodiac Hydraulic Brakes
Electric brakes are essential when towing – no matter how big or small the RV, but they are jerky and often break. Not to mention get brake dust everywhere making your wheel black.
We installed Kodiak Hydraulic brakes and they are smooth and far easier to maintain while increasing your stopping power tremendously.
This is one of those upgrades that bring a smile to face each time you press the brake pedal. To see the entire install video click here.
This is one of those upgrades you can’t believe you ever lived without, especially if you have a family, travel with dogs (safety), or your party gets split up. On many occasions, one of the boys will decide to go back to the RV early only to forget the RV keys. It’s frustrating and completely avoided by the RV Lock. Not to mention that many RV keys are the same and don’t provide a great deal of protection.
If you travel will dogs, many RVers leave their phone number on the door in case there is a problem. Should the power go out, you can always call a neighbor or the RV office and give them the code to get into your RV. You can get the RV Lock on our Amazon Page under the category “our fav RV items”.
Grand Ginger (our previous Grand Design Reflection Travel Trailer) had an outdoor kitchen with a separate electric fridge. RV fridges that run on propane have proven to be finicky – not having a back-up fridge can cost hundreds in spoiled groceries. With the Norcold fridge not working in Toy Ginger (Grand Design Momentum 399TH), we needed a back-up fridge ASAP and the Dometic 12v Cooler is 100% reliable. When we get the Norcold fridge working properly, we will covert the Dometic cooler into a half freezer half sparkling water fridge 🙂
Most shoe holders for RVs are low quality or not big enough. These are great! They come with large gromet holes and hardware and the shoe pockets are large enough for mens sneakers. This is the second time we’ve bought them and thrilled we found them online at Overtons.
When we first got Toy Ginger and needed stabilizing feet, I was going to get the large Red Anderon buckets, even though I was reluctant because of how much space they would take up. Then I learned that they were almost $300 and quickly found a far better solution. The SnapPads are permanent feet for your stabilizers which means there is one less thing to do when setting up and tearing down. It’s not a bad idea to carry some square wood boards should you need to add height, but that is only required a fraction of the time. More times than not, you can simply just lower the stabilizers and move on
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