So a few weeks back my XJR's transmission had a catastrophic failure. Knocking and rattling like crazy, then stopped going into gear at all. Shop said they found some bits of metal in the pan, most likely a planetary gear came apart. Then they said I'd need to trade an organ in to cover the costs of a rebuild, so I'm not going to do that. Called around and it seemed like the price is fair for the type of work needed, but more than I can justify spending on just a transmission on this car.

However, it'd be a damn shame to just give up on this car. If I do, I don't think I'd easily be able to get another like it later on in life, and there's still road trips I want to take on the x308. Also, mid-mileage used XJR transmissions are fairly cheap online. So, I want to try to replace it myself. Looking at the FSM, it seems like a fairly straightforward procedure to unbolt the transmission, just fiddly to undo cats, reach all the bell housing bolts, and the physical lowering/raising of the transmission once loose.

There's still a couple ducks to get in a row before pulling the trigger on that though:

1. Flushing. The shop said the transmission cooler would need flushed in case bits of metal got into there. Reasonable enough. When I stuck a dipstick in the transmission before it got towed to the shop, I didn't see any metallic particles, so it may just be big chunks in the transmission. Anyway, someone recommended a "fluid-vac" type of tool to help with flushing the transmission cooler... would this be adequate to clear it out?

2. Actually getting the transmission out. I don't have easy access to a lift, or a nearby friend with one, so I'd want to do this in the driveway, using something like the 800lb harbor-freight low profile transmission jack to do the lifting. I know the car has to get pretty high to clear the transmission, but... is it reasonably possible at all? Or should I redouble on trying to find somewhere I can borrow a lift for a few days?

Also, any other surprises in this process that could catch me off guard, that aren't in the FSM?

 

Planetaries exploding is a problem with the early 722.6 and supposedly resolved after 00. you’ll probably want to pick up a later build transmission 👍

 

You can do it in the driveway, but the exhaust system r/r is difficult. I would build cribs with 4x4 to get it high enough, and the 600 lb trans. jack will work.

 

Should be possible. I did a series 3 XJ in my driveway once. Try to drain the oil from the trans first. Spray some WD40 or similar on the nuts holding the exhaust to the cats. Support the engine with a jack, and then remove the gearbox support. lower the back of the gearbox and use a loooong extension bar to get to the bell housing bolts.

 

I had the same issue on my 98’ XJR about 3 years ago. I put in an 02’ XJR transmission and haven’t had any issues with it. One caveat though, since the trans cooler lines coming out of the transmission are banjo fittings, that makes it harder to flush out the lines. You’ll have to take the lines off the radiator to flush them out individually following the flushing of the cooler itself.

 

I had to jack mine way up to get to get the Jag spring compressor through the spring holes. Here are a couple of pics to show how to do it without a lift. The tail pipes were about a quarter-inch off the floor when I got it that high, andI was doing suspension work, but that should be enough room to get the trans out. I used 6x6 lumber.

 

Here's a search result for your area if you haven't found a trans.... https://www.car-part.com/cgi-bin/search.cgi

Don't fall over at the first few, they put gold in those when they remanned them. The ones below that aren't priced too bad. Be sure to verify mileage (as best as possible), its a 722.6 and the warranty.
Remember, these are recycle yards, you can haggle and even if your right next door to them, your on the other side of the state to have to come get it, ...so can you cut me a break?...or the old reliable...is that the best you can do?

As for getting her off the ground enough. I did similar to what Mark did, only I had my blocks under my jack stands as well, I didn't like the jack neck sticking out so high. I backed the car onto my ramps, then jacked the front up onto stands. If yours isn't driving, jack up the back and put the ramps under it.

 

ansmission issue with 308

 

Brian,

You are DEFINITELY breaking the rules. I've deleted your original post and severly pruned the quote here.

I can see you are trying to help the OP and will therefore not impose the usual 7 Day Ban in this instance. I suggest making contact through a forum PM to the OP is a better idea.

Graham

 

When you pull the transmission, I’d highly recommend replacing the rear main seal and cap seal located just above the rear main. You’ll need a 17mm Allen socket for that. I find they are actually more susceptible to leaking than the rear main itself.

 

This is extremely useful information!

Thanks everyone for the replies, gives me a bit more confidence to try this. I've looked into the results on car-part.com and might get one of those. Highhorse, the link you sent doesn't work to preserve the search parameters, but I've checked the results in my area. There's a couple that show up on both there and Ebay so I may just go the second route to make the shipping a bit simpler? I'll see. Picking up a transmission myself gets a bit tricky...

Exhaust R/I I've done before (except the cats), and replaced the hardware holding the forward muffler flanges to the cats with high quality SS nuts/bolts when the forward muffler was replaced. I'll have to pick up some 6x6 and chop it up before I start on this project.

For the rear main seal/cap, that's this part with the red arrow next to it?

 

Yes, that's the seal and plug.

 

Well I've had other things come up and delay me from this, but I think I'm finally ready and sick of putting this off...

The next question, should I look for a unit that looks to have been serviced in the past or not? I found this transmission that's low enough mileage, and looks to have been overhauled fairly recently (main body looks clean etc). If shipping is reasonable, is it worth spending a couple hundred extra bucks on this one vs a few others with similar mileage, and never having needed an overhaul?

https://www.ebay.com/itm/124362324479

 

I would ask for a photo of the vin sticker on the side of the transmission that’s not shown in the photos and run a car fax. That’s the most accurate information that you’ll ever get.

 

I can strong arm the guy if it doesn't work. I have a good friend who lives in Ball Ground, he may even know him. Its a small town NE of Atlanta....quite yuppy.

 

I'm fairly confident that the transmission was taken apart somewhat recently going off how much cleaner the main body is vs the bell housing. I may still ask him for VIN info though. Doubt any strong arming will be needed, hopefully.

I guess what I'm asking is more a general question, is it better to get a transmission that's been recently rebuilt, vs one that has been untouched from factory, but is still relatively low mileage (and slightly cheaper)?

 

The car in the video, I'm betting, is a recent auction win. He probably got it for $500 and thus reaping the rewards of parting it out.

 

I guess that makes sense, though a bit odd since I'd imagine a good condition XKR like that could fetch 15-20k used?

In any case, pulled the trigger on that one, hopefully I won't regret it. Now onto collecting all the little bits and tools, then party time!

 

 

Well everything seemed to go fairly smoothly with the physical swap. Ended up putting the jack onto some pallets for the part where I needed to raise the car high enough to roll the transmission out, and then quickly lowering it back onto the jacks for the engine work. That way you're not under the car when it's supported by a super sketchy jack-on-pallets. I ended up removing the passenger side wheel and rolling it out in that direction.

Now I've got a P0705 error which I was getting right when the old transmission went out, suspecting a bad linear switch that's just a coincidence with the transmission swap. Tried cleaning it and it worked for a little while, then threw an error again. Will have to drive more to do more diagnostics, maybe try to source a replacement.

For anyone trying this in the future, absolutely make sure to use penetrating oil on the catalytic converter studs/nuts. I'd also suggest buying a few spares for the studs (C2S9536), and replace ALL the nuts on reinstall (Mcmaster 3528N12). I tried reusing the old nuts that seemed to be in OK condition, and I wrecked one of my studs doing so when the nut seized halfway down. Had a similar issue on removal, the nut seized and took the stud out with it. Something with the way they lock in place causes the metal to come apart and jam the threads on removal. Also, it's much easier to just reach all the transmission bolts from underneath the car, if you have the arm reach, once cats are removed. Just bear hug the transmission to reach the ones up top. Much more accessible than trying to get at them from above.

Here's a rare view from underneath of the throttle body, from just after I replaced the rear oil galley plug/seal:


In any case, now I've got a broken transmission taking up space in my house. Is there any value in it? I was thinking to give the torque converter to a friend who'd chop it up and make something pretty, and I'd take the transmission itself apart to see the guts with exactly what failed. Maybe gut it and clean it, then turn it into a somewhat heavy stool.