Anyone else struggled to fit a 100Ah lithium under the bed in a Transit base?

Spent three hours lying on my kitchen floor rehearsing the exact same argument with a Fogstar 100Ah that my Transit's previous owner clearly never anticipated anyone actually using the space under.

The problem isn't the height — it's that every Transit seems to have a slightly different underbed cavity depending on which Tuesday in Swindon it was built, and none of them match the dimensions Ford actually publish. My 2019 had a rogue bit of wiring loom doing absolutely nothing useful running right through the prime battery spot, so the Fogstar ended up angled like it was doing a dramatic stage fall.

Eventually sorted it by building a small timber cradle to bridge the uneven floor and tilting the battery about 15° — checked with Fogstar support that this was fine for a lithium (it is, unlike AGM, they're not bothered about orientation). Velcro straps plus a ratchet strap over the top because I'm not having a 12kg brick becoming a projectile on the M6.

If you've got the long-wheelbase, there's supposedly more room toward the rear offside but I can't confirm that personally.

Anyone managed to squeeze a 200Ah slim-profile unit in there? Tempted by the Fogstar Drift slim cells but genuinely cannot work out if the maths works without ripping the whole bed frame out — which I'm not ruling out, to be honest.

Ha @Chopper54, I feel your pain! The under-bed space in Transits is deceptively awkward isn't it - looks generous until you're actually trying to manoeuvre something heavy and rigid into it.

One thing that saved my sanity was building a simple plywood tray with castors before the battery even arrived. Slid the Fogstar onto the tray on the garage floor, then the whole lot went under in one controlled movement rather than wrestling the battery itself.

Also worth checking whether your battery needs to go in upright orientation only - some lithiums are fine on their side which can completely change your options. The Fogstar 12V range is fairly flexible on that front if I recall correctly.

What's the actual clearance you're working with? Might be worth sharing the dimensions - someone here will have solved the exact same puzzle already.

@Chopper54 my garden office battery went in smoother than my Transit install, and that's just a shed — at this point I'm convinced Ford designed that under-bed void specifically to fit almost a 100Ah Fogstar but not quite, like some cruel puzzle from a flat-pack furniture fever dream.

@Chopper54 the "kitchen floor rehearsal" is a rite of passage nobody warns you about. I've done the same thing on my narrowboat — except on a boat you're also simultaneously discovering which muscles you didn't know existed whilst wedged at 30° in the bilge.

Worth measuring your actual cavity dimensions carefully before assuming the battery is the problem.

@Chopper54 the Transit under-bed void is a known menace — looks like 280mm clearance on paper until you factor in the frame lip, any existing cable runs, and whatever the previous owner thought was an acceptable way to route the leisure feed. I spent a genuinely embarrassing amount of time in my shepherd's hut measuring before ordering, which at least saved me the kitchen floor drama. Key thing people miss with the Fogstar 100Ah specifically: it's 260mm tall, which sounds fine until you're also trying to get a hand in to torque the terminals properly. If you can relocate it slightly further forward in the void, even 50mm, you usually get workable access. Did you check whether the Transit's crossmember is the full-width type or the partial one? Makes a significant difference to what orientation you can actually run with.