RV review: Grand Design Lineage Series M 25TK—A very impressive Class C

Today’s RV review is of the Grand Design Lineage Series M 25TK Class C motorhome. Wait, motorhome? Yep. Grand Design has heretofore only made towable RVs, but the company recently announced that they will be shipping motorhomes. In fact, this is the first example of what the company promises will be a larger line of motorhomes, including Class C and Class B (vans). 

To be quite honest, when Grand Design announced that they would be building motorhomes, I wasn’t very excited. The company has done an okay job building towables, but many of their offerings are really entry-level in structural features, in my opinion. Further, the company has really come under fire lately for issues with their frames, and they were very slow to respond to the issues. 

They have now upgraded their warranty on towable frames and, to their credit, the warranty is also transferable. Nice. 

But we’re here to look at the new Class C, and I have to say that, after learning more, I am very impressed with what they’re doing. In fact, I’m so impressed that I feel that if you are in the market for a new Class C motorhome, you’re doing yourself a disservice by not waiting to check this out. 

Grand Design Lineage

The Lineage brand is going to be applied to all of Grand Design’s motorized units. 

From a business standpoint, this makes a lot of sense because a dealership can sign up for Lineage and get the Class C and Class B and whatever else comes down the pike from Grand Design. Sometimes the RV industry so convolutes these brands that it makes it confusing for customers and difficult for dealers. 

For example, do you know the difference between a Reflection, a Transcend and an Imagine? That’s just Grand Design’s current major brand of towables. Think of the rest of the RV industry doing the same thing. I follow the RV industry, and it’s confusing for me—so I think a great deal of consolidation would not be a bad thing. 

Start at the chassis

While the company will offer more chassis options in the future, this one is built on the Mercedes-Benz Sprinter cutaway chassis. They specifically chose the 4500 series chassis, which is significant. Like with pickups, the numbers used to brand the chassis from companies bears relevance to their ability to carry cargo. 

When an RV maker builds a motorized RV, essentially, that RV is cargo on the back of the chassis. So, having greater cargo carrying capacity means that there’s additional capacity for you and your stuff. Many Class C RVs are built so close to the capacity of the chassis that there are only a few hundred pounds of remaining capacity for your stuff. 

So the objective, as described by Mike Hums at Grand Design, is that you get at least half a ton of cargo carrying capacity in your Lineage, which is respectable. 

Impressive build features in the Grand Design Lineage

Part of the way the company has worked on this is to frame interior walls and things like the dinette in welded aluminum as opposed to wood. This offers greater strength and lighter weight. 

Other weight-saving measures include the European door and the aluminum power-operated step. Little bits here and there add up, and not all of these measures are inexpensive. 

Something that really impressed me is the aluminum structure under the skin of this rig, which is an extruded aluminum channeled piece to which the walls and roof slot in. This is a really impressive way of doing this build. 

The front and rear caps on all models will be painted with automotive paint, and you can also get a fully painted exterior as an option. 

But two other things just really made me happy. 

Mike Hums described a partnership with the folks who make SharkBite plumbing fittings, which are used in this RV. Leaky, cheap plumbing fixtures are a common problem in the RV industry, so the fact that they’re using these metal fittings says a lot. 

They also have a 25-year guarantee on the plumbing of this unit. That says even more. 

Grand Design Lineage Series M 25TK - 2026

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Electrical system on the Grand Design Lineage 25TK

The electrical, too, is impressive. The standard system in this rig includes 540 watts of solar and Lithionics lithium batteries rated at 310 amp-hours. Further, there’s a 1,000-watt inverter standard. This is all backed up by a 4.5Kwh propane-fueled generator. [Note: There are different figures in Josh’s video (below) and on the Lineage Series M 25TK website, so we went with the website in case it’s been updated since the video. There… now you don’t have to report the discrepancy to us.😉]

There are also upgraded systems available, including one that uses a second alternator on the diesel engine in this coach to charge the batteries. 

But what truly blew me away is the electrical system in this rig, which uses breakers instead of fuses. So, should you experience an issue, the breaker will trip as it would in your home, but this will also illuminate a red light by the breaker. No more having to carry a bunch of spare fuses. 

“We’re spending a lot of money where people can’t see it,” said Hums. 

What’s inside the Grand Design Lineage 25TK

This is a relatively common floor plan for a smaller Class C, but the devil is always in the details on these. 

Over the cab is a bunk room that has its own A/C ducts. There is a windshield on the bunk area with a bunch of Easter eggs that someone might enjoy, including a vintage motorhome and some other things. 

The kitchen in this is exactly how trends are going with a linear two-burner propane cooktop and a convection microwave. 

The sink here is what’s referred to as a smart sink, where there are various drop-in inserts to accommodate dish washing or cleaning veggies. There’s also a glass washer where you press a glass down on the thing and it sprays water up into the glass. 

There is a good amount of cabinet space here with drawers inside the pantry, but also two huge drawers under the dinette if you choose that option. You can also get theater seats. The drawers are nicely built with dovetailed plywood construction. 

I also like that all the latches on all the doors are positive mechanical latches instead of just magnets, and the drawers feature dovetail edges. Nice. 

Magical bathroom in the Grand Design Lineage 25TK

The mid-ship bathroom is truly unique in this rig. There is a porcelain toilet and then a powder-coated aluminum cabinet with the sink and medicine cabinet. There is a segmented door on a track where you can close-off the rest of the RV. 

But then there’s a teak floor and you have a second set of segmented doors on tracks. Now you can close off the toilet and sink and, essentially, the hallway becomes the shower. Or you can leave that inner door open and have a really big shower. It’s unusual and rather impressive. 

Lastly, the A/C in this is a ducted unit that features a residential filtration system. Oh, and every light in this rig is dimmable. Plus, there are motion-sensing lights in the pantry, the rear closet and in the bathroom. 

Bedroom in the Grand Design Lineage 25TK

This RV features twin beds in the back. There is a center cushion to transform the whole bedroom into a single large king-sized bed. Each of the 36 X 80 twin beds has a power-operated adjustment for the head of the bed, which is nice.

On the camp side of this rig you can move the mattress and reveal hanging storage. Over on the road side there are larger drawers under the bed.

Conclusions

I have to say I was ho-hum about Grand Design bringing out a Class C to the market but, after looking into this, I am very impressed. The decisions made by the company seem to point to building a very high-quality product at a competitive price. 

Oh, how much? The base model is presently slated to carry a $228,776 MSRP. 

Something else worth noting: The headrests in the front seats of this rig actually have little safes in them. Talk about finding space that everybody else just ignores. 

Overall, this is one of the best Class C designs I’ve come across. I got to visit a local dealership when Grand Design was parading the Lineage around. I have to say it’s a really, really well-built and nicely designed RV. Let’s hope some of that focus on quality rubs off on the travel trailer people at Grand Design. 

My thanks to Josh from Bish’s RV for the photos and video in this story.

MORE GRAND DESIGN RV REVIEWS:

• Advanced features in the Grand Design Imagine 2800BH—Worth considering?
• RV review: Grand Design Lineage VT—a Class B!
• RV review: Grand Design Transcend 265BHT—More uses for bunk space
• A first look at a 2025 Grand Design Lineage Series motorhome

More about these RV reviews

These RV reviews are written based on information provided by the manufacturers along with our writer’s own research. They are based on information from a single unit and may not reflect your actual experience. Shop your RV and dealership carefully before making a buying decision. They are intended only as a brief overview of the vehicle, not a comprehensive critique, which would require a thorough inspection and/or test drive.

Tony comes to RVtravel.com having worked at an RV dealership and been a lifelong RV enthusiast. He also has written the syndicated Curbside column about cars. 

You can also check out Tony and Peggy’s RV podcast.

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