#lufengosaurus

I would say it is highly likely that they did! We currently have no direct evidence for or against feathers or scales on early sauropodomorphs, which means we have to rely on our understanding of other species.

We know that theropods and ornithischians posessed feathery structures at some point in their evolutionary history, and we know that pterosaurs were also fuzzy! There's actually new research that indicates pterosaur fluff does in fact share a common ancestor with dinosaur fluff, meaning all dinosaurs and pterosaurs are most likely descended from a feathered ancestor.

So what does this mean for sauropodomorphs? Well, given the earliest dinosaur was most likely feathered, early sauropodomorphs probably inherited their fluff! They were still small and vulnerable in the Triassic, and a fluffy coat like I've given this Thecodontosaurus would have helped them survive.

Image ID: Digital illustration of Thecodontosaurus, a small early sauropodomorph. It is a slender bipedal dinosaur, with a long tail and long, clawed arms. Its body is partially covered with a coat of feathers, except for the head and neck, which have bare, wrinkled skin like a turkey. The legs and belly are also bare, and coloured a pale brown. The feathers are dark brown, with white stripes on the quill-like feathers at the base of the tail. The head is mottled grey and yellow, with a blue face and red eye. Its body is turned towards the viewer, with one foot raised in an active pose. End ID.

However, as sauropodomorphs grew larger they probably outgrew their fluffy coats, as they would provide less protection than their large size already did and a heavy coat would risk overheating. Larger sauropodomorphs, such as the early Jurassic Lufengosaurus, may have had a few residual areas of fuzzy skin like today's giant mammals, but were probably scaly overall.

Image ID: Digital illustration of Lufengosaurus, a large bipedal sauropodomorph with a long neck and heavy torso and tail. The skin is scaly, except for a light dusting of feathers on the back and underside of the neck. Its body is light grey with darker spots on the back and light stripes on the tail. The neck fades to orange towards the small head, which is coloured a dark brown. The Lufengosaurus is in a walking pose, with both feet on the ground. End ID.

Source:  asklokiande; check out her blog! She does a lot of stuff with Jurassic World and does roleplay as well for the film, and reblogs a bunch of cool stuff about the franchise. Thank you so much for the lovely art!

Name: Lufengosaurus huenei, L. magnus

Name Meaning: Lufeng Lizard

First Described: 1941

Described By: Young

Classification: Dinosauria, Saurischia, Eusaurischia, Sauropodmorpha, Plateosauria, Massopoda, Massospondylidae

Lufengosaurus was a massospondylid from the Lufeng formation in Yunnan province, China. This dates to the Hettangian to Sinemurian ages of the Early Jurassic, about 190 million years ago. The main difference between the two species was size; L. huenei averaged to be about 6 meters long; L. magnus was about 9 mters long. However, they often are considered synonymous, and just two variations of size in the same species. Around thirty specimens have been discovered, including juveniles. If the two species are separate, then L. huenei was a fairly small sauropodomorph; though L. magnus was fairly large. Its forelimbs were relatively small, indicating that it was mostly bipedal, and it has been thought of as such even before most “prosauropods” were thought of as bipedal. Lufengosaurus had a deep and broad snout, and it had larger cheeks than most other sauropodomorphs. It had closely spaced, serrated teeth, indicating that it would consume large amounts of leaf matter. Though often considered in China to be a plateosaurid, it has been placed closer to Massospondylus in recent cladistic analyses. Its sharp claws may have been used for defense, and raking foliage from trees, rather than getting meat. It is fairly clear, based on the similarity of the teeth to animals such as herbivorous iguanas, that it was simply herbivorous, and meat was not a major portion of its diet. 

Sources: 

http://www.prehistoric-wildlife.com/species/l/lufengosaurus.html

https://en.wikipedia.org/wiki/Lufengosaurus