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Can I take the transmission out of my 96 Yukon and install it into my 88 Sierra SLX short wide bed
Will, Those XMSNs won’t swap. The ‘88 Sierra uses a THM400 and the Yukon uses a 4L60-E. Although the bolt pattern maybe the same, the wiring harness won’t match up and the XMSN won’t shift properly. I’d find a reputable shop that can rebuild your THM400 or clear off a spot on your bench to do it yourself. XMSN rebuilds can be tricky, however it would be a great time to add in a shift kit. Here’s a resource for the reference: https://www.transtar1.com/transmission-l… Good luck!