Jayco Jay Flight · 2023–2024340RLK

The Jay Flight 340RLK is one of Jayco's Jay Flight travel trailers, the mass-market nameplate and the volume seller in Jayco's towable range. This page covers one model year of it — the 2024 340RLK, exactly as Jayco published it — because the numbers that decide whether your truck can pull this trailer are not the same from one year to the next. Jayco publishes it at 8' 0" wide closed and 13' 11" with the slide-outs run out for the 2024 model year, which is the measurement that matters for a site pitch as well as for the road.

For the 2024 model year Jayco published a 10,350-pound GVWR on a 8,890-pound dry weight, 1,460 pounds of published cargo capacity, a 1,235-pound dry tongue weight. That dry tongue is 14% of the dry weight, inside the 10–15% band conventionally quoted for a bumper-pull trailer. Tongue weight is not fixed — it moves with how the trailer is loaded, and weight added ahead of the axles raises it. A tongue load in that range wants a weight-distribution hitch, and the tow vehicle's tongue-weight limit is a separate number from its trailer-weight limit — check the loaded tongue against the hitch receiver's rating and the vehicle's payload, not against the tow rating alone. The 2024 trailer left the factory on ST225/75R15'E' tyres; the load range in that code is part of the axle rating and a replacement set has to match it.

Against the 2023 build of the same floorplan, 7 published fields moved. The full comparison is in section 02, and it is drawn from two separate verified factory records rather than from one record and an assumption about the other.

A 2024 trailer is close to current as of 2026, but section 05 still applies: check it against its build date rather than its model year. Jayco commonly builds a model year well before the calendar year turns, and the tyre date codes have to be read against the build month, not the badge.

How the 340RLK differs from the other 122 Jay Flight floorplans. Most distinctive first. Sibling pages may cover other model years than this one (2023–2024). How these ranks are worked out.

• Cargo capacity as a share of GVWR, 14.1%: shared with the 402RLTS; of 123, five smaller and 116 larger, nearest the 401FLTS (13.7%) and the 40DLFT (14.3%).
• Dry weight, 8,890 lb: thirteenth-heaviest of 123, between the 34RSBS (8,780 lb) and the 34RLOK (8,970 lb).
• Dry tongue weight, 1,235 lb: shared with the 331BTS; of 122, 109 lighter and eleven heavier, nearest the 34RLOK (1,215 lb) and the 34RSBS (1,325 lb).
• Dry tongue weight as a share of dry weight, 13.9%: twentieth-largest of 122, between the 178DBS (13.8%) and the 178DBSW, 242BHS and 261BHSW (14%).
• Black tank, 32.5 gal: shared with the 210QBW and 331BTS; of 121, sixteen smaller and 102 larger, nearest the 180LK and 180LKW (20 gal) and the 130BH, 130RD and 79 others (39 gal).
• GVWR, 10,350 lb: 23rd-highest of 123, between the 31QBDS (10,250 lb) and the 331BTS (10,400 lb).
• Length, 37 ft 10 in: shared with the 331BTS, 333BTS and three others; of 123, 102 shorter and fifteen longer, nearest the 34RSBS (37 ft 8 in) and the 325BHT (38 ft 4 in).
• Sleeping capacity, 4: shared with the 130BH, 130BHW and 23 others; of 110, five smaller and 79 larger, nearest the 140TB, 140TBW and three others (2) and the 174BH, 212QB and four others (5).
• Cargo capacity, 1,460 lb: 38th-smallest of 123, between the 264BH (1,445 lb) and the 224BHW (1,480 lb).
• Exterior height, 10 ft 5 in: shared with the 211MBW, 240RBS and ten others; of 109, 47 lower and 49 taller, nearest the 235MBH, 242BHS and 263RBS (10 ft 4 in) and the 210QB, 235MBHW and four others (10 ft 6 in).
• Grey tank, 39 gal: shared with the 140TB, 172DB and 48 others; of 118, 27 smaller and 40 larger, nearest the 21QB (33 gal) and the 130RDW, 172DBW and seventeen others (40 gal).
• Fresh tank, 52 gal: shared with the 200MKS, 210QB and 47 others; of 123, 31 smaller and 42 larger, nearest the 40LOFT (51 gal) and the 40FKDS (53 gal).

Next to the 34RSBS (2018–2023 page), the nearest lighter floorplan by dry weight, the 340RLK is 110 lb heavier by dry weight, has a GVWR 900 lb lower, has 1,010 lb less cargo capacity, has a dry tongue weight 90 lb lighter, is 2 in longer, stands 3 ft 8 in taller, has a fresh tank 28 gal smaller, has a grey tank 32.5 gal smaller, has a black tank 6.5 gal smaller and sleeps two fewer; the two publish the same interior height.

Next to the 34RLOK (2023 page), the nearest heavier floorplan by dry weight, the 340RLK is 80 lb lighter by dry weight, has a GVWR 1,000 lb lower, has 920 lb less cargo capacity, has a dry tongue weight 20 lb heavier, has a fresh tank 28 gal smaller, has a grey tank 39 gal smaller and has a black tank 6.5 gal smaller; the two publish the same length, exterior height, interior height and sleeping capacity.

This floorplan has a published factory record for 2 model years here, 2023 to 2024. The specification does not hold still: dry weight runs from 8,770 lb (2023) to 8,890 lb (2024); dry tongue weight runs from 1,175 lb (2023) to 1,235 lb (2024). Each year’s complete record is printed separately below, carrying only that year’s own published figures and source. Nothing is copied across from a neighbouring year.

Jayco changed 7 of the published fields between the 2023 and 2024 340RLK. Every figure in both columns is that model year's own factory record — nothing here is carried across from the other year.

A full 52-gallon fresh tank is about 432 lb of water (water counts as cargo: 49 CFR 571.120 S10.4.2), 30% of the 340RLK’s 1,460 lb cargo capacity, leaving 1,028 lb (257 lb per rated berth). Across 123 Jay Flight floorplans the water share runs 13% to 47%, and 39 give up more than this one. Nearest on that share: Jay Flight 28RLS at 29% and Jay Flight 264BH at 30%. Your own unit’s figure is on the label inside its entry door (49 CFR 571.120 S10.4.3).