I stopped by the transmission shops owners house today to drop by some deer chili (friend of the family) and asked him what he recommended in the T5 transmission. This is a guy who has 5 or 6 Jeeps himself out behind their large transmission shop in their storage yard, including a serious CJ7 hill-climber that has had the front frame extended like 6-7 feet, it's almost half again longer than a regular CJ7 and I've got video of him taking it to a local 5000 acre offroad area and climbing a 10 foot high bank that is literally straight up. Anyways, he also suggested the Synthetic 75W90 but he didn't recommend the Valvoline as his personal choice, he specifically recommended the Lucas oil pure synthetic. I noticed the Valvoline only meets one or two specifications according to the bottle but the Lucas says it meets numerous specs and is safe for the brass in my transmission. He told me it will shift smoother and I would really like it better than anything else in a T4 or a T5. So I picked some up and just did my change, took a short drive and I can feel the difference, it's noticeably smoother. I forgot to ask what he would recommend for the D300 and my axles... Would be nice to use the Lucas in all of them, but which weight/thickness?
~ SouthernGypsy's Jeeps ~
2004 Jeep TJ Rubicon 4.0L/Automatic
1983 Jeep CJ-7 Limited 4.2L/5 Speed