Hobbes

Hello to all dealing with questions and doubts about differentials! If you are ever in doubt, contact Jim Mitschke: J D Race & Restoration Muscle Car Differential Specialists Richfield, Oh 44286 330 990 8155 He also owns a First Gen Monte SS (forgot the exact year) and he knows a hell lot about diffs. In fact that is also his business. He is polite and very very helpful. He was the one pointing me also in the right direction to find out that my Monte has a BOP axle and diff even originally installed in the factory and documentated in the buildsheet due to the strikes in that year. If you are looking for BOP posi and parts you will realize it is a demoralizing way in respect to prices and availability. Jim can give you advice in the pros and cons of sticking to BOP or changing to a Chevy axle. Good luck to you raceking46! I have lying in my garage all the pieces for changing gears and posi over a year now. My next quest is now to find a trustful guy here in Hamburg (Germany) to help me installing it right Janin

Salutes to this fine work....!! Janin (You make it hard to show my trunk in the progress now... )

Dan, thanks for the dash assembly picture. All others, thank you for the information given. I am looking forward to Steve's pictures he sent to Rob. Please don't try to take apart the sensing unit, or it will look like mine... the tube missing, the hole in the reservoir tapped and the rest left hanging around by the previous owner .... As I will try to rebuild the system to work again, you bet I will take pictures to provide you... I already got a bottle of wine for the cork's new destiny as a floater and the wine for some inspiration..... JAnin

Hey Dan the top part assembly with the bulbsocket looks the same! The tube that goes into the reservoir is missing. I guess it broke off. Later when I am in the garage I will take a picture. I still didn't come up with a simple mechanism that would let 3 different colors slide through the bulb being on top and the floater downwards.... So maybe I stick with your setup. A cover that slides down and when it is low it lets a light shine through the fiber. Basicly only showing a light when it is low.... Could you also take a picture for me of the assembly under the dash? So I can try to make it look as close to original as possible? That would be great. Hope all is fine on your side of the ocean... I am right now struggeling with the windows to get in without breaking my patience.....it looked sooo self explaining when getting them out... JAnin

Hey RichG, thank you for the detailed answere... I have a good clue now... A tube, a floater and some colored foil/plastic. Is it possible to post a picture because there is one uncertainty I have: If the floater is on top because the reservoir is full, how does it work that only green shines through? I mean, how do the colors slide in the tube to shine through the bulb at the top? I think I just have knot in my mind. Here is a simple scematic of where I stand. Maybe looking at yours can help me untie it. I am not drawing much with the computer and I am not near the Monte to check. Just my memory. But I think it shows where my knot is.

Hello wise folks out there, assembling the Monte I found 90% of my washer fluid monitor system hanging in the engine compartment. I am only missing the tube with the sensing unit that goes into the reservoir and the assembly where the fiber optic cable under the dash (driver's side) hooks into. The assembly on top with the cables and the bulb is there. I want to make the system work again. In the books I have, there is no info on how exactly the sensing unit works. I am sure it is something I can built myself if I only knew how it works... Any ideas or suggestions? Thanks in advance Janin

Oh, and here a good reason for picking on Euro options on US cars...the two just don't work together: A pic from my stock '2-barrel-Euro-castration-carb' in comparison to the eddi 600cfm I will put on.... I wonder how the car could even run with so little... Janin

Hey Dan, thanks for searching the net for me and actually finding some better infos than me! What a coincidene! I am writing mails with J.Mitschke already. I found the JDRace.com page and got good qualified answeres to my BOP Rear. And guess what: J.Mitschke has a 71SS Monte!!! He also had a good explanation why my Potiac Tempest rear got in the Monte. He said in 1970 there were a lot of strikes going on, and the assembly lines took any GM rear that were available. If anybody has rear end questions, I can recomend the JDRace.com page. They are specialised in GM muslecar rears only! And he takes the time in answering proper. Not like the so many standarised computer answeres I got from other sites. And to your question on the option. I assume it is the elecctric seat back lock. I think, but I am not sure, just playing puzzle, that it is the locking mechanism of the front seat operated by one of those 2 door pins. When I close the door the front seats lock, so they can't lean forward while driving. I hear a strong "click" when closing the door. It took a while to figure that out because all my friends want to ride in the front and we squeeze all in there. One time somebody got in the back and found the source for that click comin from the seat. But I am not sure if I take that option wrong. Oh, and my door edge guards are not there anymore... My 8 Track AM player is stored safe. With time and money I want to sent it to a guy that fully restores the old GM radios and puts line in/out and other newer features in it with keeping the old tube/transistor mehanism alive. He only does old GM radios at his pace. I just hope I will be able to do so before these guys with their eligable knowlegde and experience all die. To give you a price on him, a full service is not below 450-500USD. If anyone interested I can find that link and paste it here. Back to my rear: I belive it is less hazle to keep my rear also for the originality of my car. Since I am not planing on racing I won't abuse it too much. Only at the red lights fuming my oponents of course! So maybe I have to spend more $$$ for internal parts, but that rear end is not a weak one for my purpose. So long Janin

Hey Monte7071! Yep, all options are there. Or at least a trace of it. The only things missing: -window washer monitor (completely gone, but lookig to get one!) -power trunk: wires cut, but hardware still there (also looking for parts to restore it) -air ride system was there but cut off at the wires and airline. That option was out of my league to make it work again, so I sold it to a member here to fund some of the other parts I needed) except for the factory clock and above stated everything works, all the litle map trunk whatever lights,power bench, windows...it amazes me! I just repaired the rear defogger...it was only dirty... Well, to be honest: I have no clue what an engine block heater looks like but I stumbled across it deciphering my buildsheet.. Axle wise: like I said. I am right now balancing the pros and cons. Pro: -original axle -good shape (assuming the total (1)17800 km = 63600mls from the speedo reading is right)and feels tight -I have it Cons: -parts are hard to get -very expensive!!!!!!! -just not the gearing/carrier I want Can you just give me a rough estimate on used/rebuilt 10bolt chevy axles? Online on the official vendors places I see prices like for a rebuilt one with my dream specs for around 1500USD. If those are the numbers I have to count with, I guess I stay with my BOP. Janin

Hey there, for the skeptic among you, here is a pic of the buildsheet, with the readable info on axle, posi, auto level and smallest engine... plus the axle codes info on the Tech section lists the "xc" code, with the odd ratio of 2.78 So I still think it is the axle with which the Monte rolled off the assembly line in 1970. I know these are odd combinations, but hey, this car went straight from factory to switzerland. Km/h speedo plus a original GM but funny swiss/german version of the owners manual. And as a side note: this may be the smalles engine in the Monte line, but it is HUGE compared to engines out there at that time. If I just compare my 1300cc VW Bug from 1968 with the MOnte, it must have been a monster on the streets. The two cars seem decades apart technical wise, not only 2 years... At the end another question: I did some homework on the BOP parts. With posi-carrier for gearing I want, ring and pinion and rebuild kit I am facing easily 800USD... I am wondering what used/rebuild Chevy 10 bolt axles go for in the US? I am just trying to figure out pros and cons of rebuilding my BOP axle or get a 10 bolt chevy one where parts are cheaper and there is more available.... Here in Europe they are hard to find or very expensive due to the small market. Shipping wise for items that big, I am not concerned, because I get freight benefits since I am working for an airline. I would roughly pay 1,2Euros/kilo (1Kilo around 2 Pounds) once the axle is within an bigger/international airport... I appreciate any input... Janin

Monte70car and Bones, thx for quick reply...and OUCH... that is definately not what I wanted to hear...new carrier with posi and gears that are hard to get... That rips an unexpected hole in my pocket... I will definately have to unbolt that diff-cover trying to find proof for you guys being wrong... But at least now I can start looking for proper parts...OUCH, my eyes...that can't be true, they must have forgotten a decimal point there... I just wish my junkyard was filled with different cars than VW Golf2, Opel Astras, Fiats, Renaults and all that stuff that is sooo wrong frontdriving... So far I appreciate all the secret book hints and info-tips. I will be back...when the differential is open with some pics and probably some more questions. Great Place Here, Thx! JAnin

Hey all there... thx for the support on infos. Bones, your axle code pic is from a storybook where the world lives in peace Frustated on all the confusing different axle options and not yet willing to open the differential or getting off the driveshaft, we grabbed the steelbrush and looked everywhere. Now it gets spooky : number found on the drivers side facing to the rear.... plus it is shorter than expected. At least from the code list on the Tech info site it states the strange gearing of 2.78, which is also stated in my buildsheet. I hope someone here has a secret book with information he would have to kill that one that sees the book.... Because with that number still I am not sure weather it is a 8.5" or 8.2" axle and if the carrier will hold up those richmond 3.42 gears I am dreaming of... Janin

Hey Bob, that is an approach to try. I have the dilemma though, that I don't want to tear the rear apart. We still need the Monte to drive to the friend's garage and I hoped to get the parts before that. Have there been 8.2" axles on the 70s Montes in the first row? In worst case I have to take off the driveshaft to look up that pinion nut. But that at least saves me from opening the differential. I also wrote a mail to Richmond Gears, asking about that carrier. In my summit catalog it has NO sidenote about carriers. Just seems as if with the 8.5" axl it should fit...if I have a 8.5"..... uargh....too many ifs and whens...

Hey Robert, You are right. Important info missing. Here it comes: got a TH350 and a 10 bolt rear. The tag at the rear states to use correct fluid for limited slip. The buildsheet says G80 - Positraction ?! And like I said, there is no way to read digits on the axle. Heres a pic of the rear with the limited slip tag. Both tires spin the same way, there is no delay when we tried while the back was lifted up. The carrier question bothers me, because I can find little sidenotes in the catalogs like: 2.73 and up or 2.5something and down carrier. Since my buildsheet says 278 ratio axle I am assuming the carrier for the bigger gears equipped with the lowest one. But just not sure and not wise enough how to find out. Any ideas? Janin

Hey Ken, thx for the input. I was a little undecided since I read a recent post here from someone going back to a lower gear ratio because he didn't like the steep gears.... And a single tire spin is not a burn out in my diccionary...positraction is a must! burn baby, burn.... JAnin