Ok now GWR and SWR have sprinters and I would like to know who can tell the difference between the class 158 and 159 because they look identical.
Big difference is the 159 has first class, the 158 does not (at least that's how it was when they were built, Trans-Pennine put first class in their 158s, I think the only company to do so)
Long story short is that NSE could not obtain 158’s from BREL because of some disagreements regarding the required specifications, mainly regarding having first class, so another company (Babcock Rail) built the 159 with NSE’s desired specs. There are differences such as bogies, couplers and toilets, but as for any distinctive differences, there are none, barring that 159’s have first class where 158’s do not, regarding TPE, those 158’s were rebuilt/modified and renumbered as 159/1’s. Other than you might find a 159 & 170 coupled, where as you wouldn’t see such a consist with a 158, although I don’t think that would be seen at all now since the 159 fleet was bolstered with the modified 158’s from TPE, so the 170’s aren’t needed. Also all of the 159 fleet is in service with SWR, so you won’t see a 159 outside of their routes and liveries.
I think I read that SWT were having issues with the 170s (not sure what) so got some of the ex-TPE ones when TPE got the 185s.
Yeah those ones are the 159/1’s, it was essentially a swap with TPE getting the majority of the 170’s, around half of those subsequently went to Chiltern Railways.
Poor reliability compared to the 159s - Salisbury's 159 fleet's reliability was legendary, the 170s couldn't match it no matter what Salisbury did. SWT also were looking for additional trains for the new hourly service to Exeter and wanted gangways as these services had catering. So 8 170 lemon and 2 ex-CT 158s were swapped for 18 ex TPE 158s, all got a high quality refit - the 2x2 TPE First class was replaced with 2+1 using the same seats as in GNER's Mallard refurbs. And within a year or so the reliability was up in the 100,000mpc area - instead of 20,000 with TPE. Mind you SWR pretty much killed Salisbury's preventative maintenance regime so reliability on the 159s has plunged now. As for differences between a 3 car 158 and a 159, very few - 159s were Network South East spec 158s. As for why the new class, NSE had a slightly different brake setup which may have affected compatibility with 'standard' 158s - turned out not to be an issue - also 158's already had a /9 variant and so instead of a /10 they went to 159/0. SWT renumbered the ex-TPE 3 cars as 159/1s and the 158s were renumbered in the 1588x. This was to standardise things from a fleet management perspective - 159 = 3 car 158 = 2 car.