Rembrant Posted October 25, 2018 Share Posted October 25, 2018 Folks, Dumb question, I know...but would a 1986 F150 4x4 have a 9" rear end or 8.8? I thought by 1986 all of the 1/2 ton trucks had the 8.8 rear? PS: Gary, I went to the Driveline > Differentials > Rear differentials page, and it comes up blank. Is it one that is under construction, or is it complete but "broken"? (Or did I do something wrong?). Link to comment Share on other sites More sharing options...
Gary Lewis Posted October 25, 2018 Share Posted October 25, 2018 Hmmm. Looks like you found a big gap in the information. There's also a page on Rear Axles, but it isn't complete. I'll work on that, probably tomorrow night during the World Series, and will hope to consolidate or at least refer from one page to the other. As for whether an '86 had a 9" or an 8.8", it looks to me like the catalog says it could be either. Here's the entry for F100's and F150's, and the WDM and WFE axles are, as it says, the 9". And they were used through '86. But, from what I see, if the rear axle is the lighter-duty one, meaning rated for 2,800 lbs, then it will be a 9" since the 8.8" only came with a 3,750 rating. Now I need to record this, and the similar info about the F250/350 rear axles, in the Y2Y Differences page. Link to comment Share on other sites More sharing options...
Rembrant Posted October 25, 2018 Author Share Posted October 25, 2018 Hmmm. Looks like you found a big gap in the information. There's also a page on Rear Axles, but it isn't complete. I'll work on that, probably tomorrow night during the World Series, and will hope to consolidate or at least refer from one page to the other. As for whether an '86 had a 9" or an 8.8", it looks to me like the catalog says it could be either. Here's the entry for F100's and F150's, and the WDM and WFE axles are, as it says, the 9". And they were used through '86. But, from what I see, if the rear axle is the lighter-duty one, meaning rated for 2,800 lbs, then it will be a 9" since the 8.8" only came with a 3,750 rating. Now I need to record this, and the similar info about the F250/350 rear axles, in the Y2Y Differences page. OK Gary, thanks. I was just looking at pics of a 1986 F150 4x4 that showed up for sale locally last night. It appears to have a 9" rear diff in it, and I thought by 86 that they ALL had the 8.8 rear diff. That's all, no big deal. Thanks. Link to comment Share on other sites More sharing options...
Gary Lewis Posted October 25, 2018 Share Posted October 25, 2018 OK Gary, thanks. I was just looking at pics of a 1986 F150 4x4 that showed up for sale locally last night. It appears to have a 9" rear diff in it, and I thought by 86 that they ALL had the 8.8 rear diff. That's all, no big deal. Thanks. I'm glad you asked the question as it pointed out a large hole in the info on the website. Link to comment Share on other sites More sharing options...
PetesPonies Posted October 26, 2018 Share Posted October 26, 2018 I'm glad you asked the question as it pointed out a large hole in the info on the website. I have had people tell me they had '86s and maybe even '87s with a 9". I do believe at least by '88 they were all 8.8s. Link to comment Share on other sites More sharing options...
Gary Lewis Posted October 26, 2018 Share Posted October 26, 2018 I have had people tell me they had '86s and maybe even '87s with a 9". I do believe at least by '88 they were all 8.8s. I won't say they couldn't have had a 9" in an '87. The master parts catalog indicates they weren't using them, but I'm sure Ford didn't throw anything away when it would bolt right in. The MPC says that slide locks ended in March of '81, but I've documented trucks that were built as late as July of '81 that came with slide locks. I think they just used up whatever supply they had of the locks. So it is quite probable that Ford continued to use whatever supply of 9" axles they had until they ran out, and that surely varied by the manufacturing plant. Link to comment Share on other sites More sharing options...
Gary Lewis Posted October 27, 2018 Share Posted October 27, 2018 I won't say they couldn't have had a 9" in an '87. The master parts catalog indicates they weren't using them, but I'm sure Ford didn't throw anything away when it would bolt right in. The MPC says that slide locks ended in March of '81, but I've documented trucks that were built as late as July of '81 that came with slide locks. I think they just used up whatever supply they had of the locks. So it is quite probable that Ford continued to use whatever supply of 9" axles they had until they ran out, and that surely varied by the manufacturing plant. I revised things a bit. Discovered I had both a Rear Axles page as well as a Differentials page. There is now one page: Driveline/Axles & Differentials and it has the info from both of those pages. And those pages have been deleted, and a redirect to the new page created so if someone had the old ones bookmarked they'll still find the info. I'm not really done with this new page, but it is an improvement - I think. Link to comment Share on other sites More sharing options...
Bulldawg1081 Posted October 30, 2018 Share Posted October 30, 2018 Maybe this will help.. I've been building these trucks for over 20 years.. in MY experience all 1/2 ton bullnose trucks up through 1982 came with a 9" rear no matter what engine it had.. 1983 through 1986 if the truck was a 300/6 or a 302 it came with an 8.8 BUT the 351w trucks still came with a 9".. I currently have an 86 302 truck with an 8.8 and two 86 351w trucks with factory 9" rear ends. Also you'll notice the 9" 3rd members from 83 to 86 have a longer yolk than previous years to accommodate the longer snout of an 8.8 so that driveshafts are universal. Link to comment Share on other sites More sharing options...
Rembrant Posted October 30, 2018 Author Share Posted October 30, 2018 Maybe this will help.. I've been building these trucks for over 20 years.. in MY experience all 1/2 ton bullnose trucks up through 1982 came with a 9" rear no matter what engine it had.. 1983 through 1986 if the truck was a 300/6 or a 302 it came with an 8.8 BUT the 351w trucks still came with a 9".. I currently have an 86 302 truck with an 8.8 and two 86 351w trucks with factory 9" rear ends. Also you'll notice the 9" 3rd members from 83 to 86 have a longer yolk than previous years to accommodate the longer snout of an 8.8 so that driveshafts are universal. Well now I know! I thought that all of the half ton trucks had the 8.8 diff from 83 up, but I did just see an 86 4x4 with a 302 and a 9" rear diff. Interesting stuff. I like finding out these details, thanks! Link to comment Share on other sites More sharing options...
Gary Lewis Posted October 31, 2018 Share Posted October 31, 2018 Maybe this will help.. I've been building these trucks for over 20 years.. in MY experience all 1/2 ton bullnose trucks up through 1982 came with a 9" rear no matter what engine it had.. 1983 through 1986 if the truck was a 300/6 or a 302 it came with an 8.8 BUT the 351w trucks still came with a 9".. I currently have an 86 302 truck with an 8.8 and two 86 351w trucks with factory 9" rear ends. Also you'll notice the 9" 3rd members from 83 to 86 have a longer yolk than previous years to accommodate the longer snout of an 8.8 so that driveshafts are universal. I just confirmed that in the 1984 facts book. It says that everything but the 351's got 3.55 gears, but the 351's got 3.50's. That obviously means the smaller engines were backed by 8.8's and the "big" 351's got 9" gears. Link to comment Share on other sites More sharing options...
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